Gr 9 NATURAL SCIENCES: Term Test 3

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Questions and Answers

What type of force occurs when an object is being squashed or deformed by forces acting towards each other?

  • Tension
  • Friction
  • Normal Force
  • Compression (correct)

What is the primary factor affecting the gravitational force between two objects?

  • Color of the objects
  • Mass of the objects (correct)
  • Shape of the objects
  • Distance between the objects

What is the direction of the gravitational force between two objects?

  • Perpendicular
  • Parallel
  • Repulsive
  • Attractive (correct)

What is the primary characteristic of magnetic forces?

<p>They act over a distance (D)</p> Signup and view all the answers

What determines the direction of a magnetic field?

<p>The poles of the magnet (A)</p> Signup and view all the answers

What is responsible for the electrostatic force between two objects?

<p>Transfer of electrons (B)</p> Signup and view all the answers

What is the result of friction between two objects in terms of electrostatic forces?

<p>One object becomes positively charged, the other negatively charged (D)</p> Signup and view all the answers

What type of force is responsible for the attraction between the Earth and objects on its surface?

<p>Gravitational force (B)</p> Signup and view all the answers

What is the formula for calculating the weight of an object on Earth?

<p>W = m × g (C)</p> Signup and view all the answers

What is the term for forces that act between objects without physical contact?

<p>Non-contact forces (D)</p> Signup and view all the answers

What is the definition of a force?

<p>A force is a push or pull on an object (A)</p> Signup and view all the answers

What is the unit of measurement for force?

<p>Newton (C)</p> Signup and view all the answers

What is the effect of forces on an object's motion?

<p>Start or stop the motion, increase or decrease its speed, or change its direction (A)</p> Signup and view all the answers

What is acceleration?

<p>The rate at which an object's velocity changes over time (A)</p> Signup and view all the answers

What happens when one object exerts a force on another object?

<p>The second object exerts an equal and opposite force back (A)</p> Signup and view all the answers

What is the result of balanced forces?

<p>The net force is zero (C)</p> Signup and view all the answers

What is the result of unbalanced forces?

<p>The net force is greater than zero, causing motion (C)</p> Signup and view all the answers

What is an example of action and reaction forces?

<p>You pushing against a wall (B)</p> Signup and view all the answers

What is the purpose of the salt bridge in the zinc-copper cell?

<p>To connect the two half-cells (C)</p> Signup and view all the answers

What happens to the zinc metal at the anode?

<p>It loses electrons and becomes zinc ions (D)</p> Signup and view all the answers

What is the definition of electric current?

<p>The rate of flow of electric charge in a circuit (C)</p> Signup and view all the answers

What is the unit of measurement for resistance?

<p>Ohms (A)</p> Signup and view all the answers

What is the purpose of an ammeter or voltmeter in the zinc-copper cell?

<p>To observe the ammeter or voltmeter reading (D)</p> Signup and view all the answers

What happens to the copper ions at the cathode?

<p>They gain electrons and become copper metal (D)</p> Signup and view all the answers

What is the relationship between current, voltage, and resistance described by?

<p>Ohm's Law (D)</p> Signup and view all the answers

What is a conductor?

<p>A material that allows electric charge to flow through it easily (A)</p> Signup and view all the answers

What is the flow of electrons in an electrical conductor due to?

<p>Delocalised electrons (D)</p> Signup and view all the answers

Why does resistance occur in an electrical circuit?

<p>Due to the opposition to the flow of electrons (A)</p> Signup and view all the answers

What is the main difference between gravitational force and electrostatic force?

<p>Gravitational force is always attractive, while electrostatic force can be attractive or repulsive. (A)</p> Signup and view all the answers

What is common to all three field forces?

<p>They are all non-contact forces that can be represented by fields and field lines. (D)</p> Signup and view all the answers

What is the purpose of a salt bridge in a voltaic cell?

<p>To connect the oxidation and reduction half-cells of the voltaic cell. (C)</p> Signup and view all the answers

What is the role of an electrolyte in an electric cell?

<p>To produce an electrically conducting solution when dissolved. (B)</p> Signup and view all the answers

What is the primary function of an electric cell?

<p>To convert chemical energy into electrical energy. (C)</p> Signup and view all the answers

What is the difference between an electric cell and a battery?

<p>An electric cell is a single device, while a battery is a group of devices. (D)</p> Signup and view all the answers

What is the purpose of the zinc nail in the simple lemon battery experiment?

<p>To act as one of the electrodes in the electrochemical reaction. (B)</p> Signup and view all the answers

What is the role of the lemon juice in the simple lemon battery experiment?

<p>To act as the electrolyte in the electrochemical reaction. (C)</p> Signup and view all the answers

What is the main difference between an electric cell and a mechanical generator?

<p>An electric cell relies on chemical reactions, while a mechanical generator relies on mechanical energy. (D)</p> Signup and view all the answers

What is the main purpose of a resistor in an electrical circuit?

<p>To convert electrical energy into other forms (D)</p> Signup and view all the answers

What happens when electrons collide with the atoms of a conductor?

<p>They transfer kinetic energy (B)</p> Signup and view all the answers

What is the symbol used to represent a resistor in a circuit diagram?

<p>[[image of a resistor]] (A)</p> Signup and view all the answers

What is the purpose of a rheostat?

<p>To control the current in a circuit (A)</p> Signup and view all the answers

What type of component is used to control the current flow through an LED?

<p>A resistor (D)</p> Signup and view all the answers

What is the main difference between incandescent bulbs and LEDs?

<p>Their efficiency (D)</p> Signup and view all the answers

What is the direction of current flow through a diode?

<p>In one direction (C)</p> Signup and view all the answers

What is the term for the energy that is wasted as heat in a system?

<p>Wasted energy (C)</p> Signup and view all the answers

What is the purpose of a resistor in a circuit with an LED?

<p>To protect the LED from high currents (D)</p> Signup and view all the answers

What happens to the current in a circuit when the resistance is increased?

<p>It decreases (C)</p> Signup and view all the answers

What is the main characteristic of a series circuit?

<p>It has only one path for electric current (D)</p> Signup and view all the answers

What happens to the total voltage when cells are connected in series?

<p>It increases (B)</p> Signup and view all the answers

What percentage of input energy is wasted as heat in an incandescent bulb?

<p>90% (B)</p> Signup and view all the answers

How do you measure the potential difference in a circuit?

<p>Using a voltmeter (A)</p> Signup and view all the answers

What is the purpose of an ammeter?

<p>To measure the electric current (C)</p> Signup and view all the answers

What is the term that determines a material's ability to conduct electricity?

<p>Resistivity (D)</p> Signup and view all the answers

How does the length of a conductor affect its resistance?

<p>It increases the resistance (C)</p> Signup and view all the answers

What happens to the total resistance when resistors are connected in series?

<p>It increases (A)</p> Signup and view all the answers

What is the main characteristic of a parallel circuit?

<p>It provides multiple paths for electric current (A)</p> Signup and view all the answers

What is the effect of increasing the temperature of a conductor?

<p>It increases the resistance (C)</p> Signup and view all the answers

How does the temperature affect the resistance of conductors?

<p>It increases the resistance (D)</p> Signup and view all the answers

What is the formula to calculate the resistance of a conductor?

<p>R = ρL/A (D)</p> Signup and view all the answers

Why is copper a better conductor than iron?

<p>Copper has a lower resistivity (D)</p> Signup and view all the answers

What is the effect of longer conductors on resistance?

<p>It increases the resistance (A)</p> Signup and view all the answers

How do you connect a voltmeter to measure the potential difference?

<p>In parallel with the component (C)</p> Signup and view all the answers

What is the effect of a thicker conductor on its resistance?

<p>It decreases the resistance (B)</p> Signup and view all the answers

What happens to the resistance of a conductor when its cross-sectional area is increased?

<p>It decreases (A)</p> Signup and view all the answers

What is the purpose of connecting cells in series?

<p>To increase the total voltage (A)</p> Signup and view all the answers

Why does the filament in an incandescent bulb heat up?

<p>Due to the high resistance of the filament (D)</p> Signup and view all the answers

What are the four primary factors that affect the resistance of a conductor?

<p>Type of material, length, cross-sectional area, and temperature (D)</p> Signup and view all the answers

What happens to the total resistance when resistors are added in parallel?

<p>It decreases (B)</p> Signup and view all the answers

What is the advantage of connecting cells in parallel?

<p>Stable voltage and increased battery life (A)</p> Signup and view all the answers

What is the relationship between the total current and the currents in each branch in a parallel circuit?

<p>I_total = I_1 + I_2 + I_3 (C)</p> Signup and view all the answers

What is the purpose of using parallel circuits in homes?

<p>To allow multiple devices to operate independently (C)</p> Signup and view all the answers

What happens to the potential difference across each branch in a parallel circuit?

<p>It remains the same as the potential difference across the battery (C)</p> Signup and view all the answers

What is the effect of adding more devices in parallel circuits?

<p>It has no effect on the overall resistance (C)</p> Signup and view all the answers

Why do parallel circuits provide a practical way to manage electricity in homes?

<p>They allow multiple devices to operate independently (A)</p> Signup and view all the answers

What is the risk of overloading parallel circuits?

<p>It can cause a fire or electrical shock (D)</p> Signup and view all the answers

What does the direction of an arrow represent when forces are represented using arrows?

<p>Direction of the force (C)</p> Signup and view all the answers

Which law is used to measure forces using a spring balance?

<p>Hooke's Law (D)</p> Signup and view all the answers

What type of force is friction an example of?

<p>Contact force (A)</p> Signup and view all the answers

What is the normal force equal to on a flat, level surface?

<p>Equal to the weight of the object but in the opposite direction (C)</p> Signup and view all the answers

What is the net force if a force of 7 N and 10 N are applied to an object, and friction is 5 N?

<p>12 N (D)</p> Signup and view all the answers

What is an advantage of friction in movement?

<p>It allows us to walk without slipping (A)</p> Signup and view all the answers

What type of force is the force of gravity between two objects an example of?

<p>Non-contact force (A)</p> Signup and view all the answers

What is the force that opposes motion between two surfaces in contact?

<p>Friction (C)</p> Signup and view all the answers

What is the force that occurs when an object is being pulled by forces acting from opposite ends?

<p>Tension (D)</p> Signup and view all the answers

What is an example of a non-contact force that can exert a force on each other without touching?

<p>Magnets (D)</p> Signup and view all the answers

What is the effect of forces on an object's motion?

<p>It can change the object's speed, direction, or both (C)</p> Signup and view all the answers

When do action and reaction forces occur?

<p>When one object exerts a force on another object (D)</p> Signup and view all the answers

What is the net force when multiple forces act on an object?

<p>The combined effect of all the forces (B)</p> Signup and view all the answers

What is the result of unbalanced forces?

<p>The object will change its motion (D)</p> Signup and view all the answers

What is the definition of acceleration?

<p>The rate of change of an object's velocity (C)</p> Signup and view all the answers

What is the unit of measurement for force?

<p>Newton (B)</p> Signup and view all the answers

What is an example of a force that can change an object's shape?

<p>Pushing or pulling (A)</p> Signup and view all the answers

What happens when the forces acting on an object are balanced?

<p>The object will remain stationary (D)</p> Signup and view all the answers

What is the main difference between tension and compression forces?

<p>Tension forces stretch an object, while compression forces squash an object. (D)</p> Signup and view all the answers

What is the force of attraction between any two objects with mass?

<p>Gravitational force (C)</p> Signup and view all the answers

What is the formula for calculating the weight of an object on Earth?

<p>W = m × g (B)</p> Signup and view all the answers

What is the term for forces that act between objects without physical contact?

<p>Field forces (A)</p> Signup and view all the answers

What is the nature of magnetic forces?

<p>Like poles repel, and opposite poles attract (D)</p> Signup and view all the answers

What is the nature of electrostatic forces?

<p>Like charges repel, and opposite charges attract (D)</p> Signup and view all the answers

What is the force that acts between charged objects?

<p>Electrostatic force (A)</p> Signup and view all the answers

What is the result of friction between two objects in terms of electrostatic forces?

<p>Electrons are transferred from one object to another (D)</p> Signup and view all the answers

What is the primary characteristic of field forces?

<p>They act over a distance (C)</p> Signup and view all the answers

What is common to all three field forces?

<p>They act over a distance (D)</p> Signup and view all the answers

What is the purpose of a spring balance in measuring force?

<p>To stretch in proportion to the force applied (D)</p> Signup and view all the answers

What type of force occurs when objects are not in physical contact with each other?

<p>Non-contact force (D)</p> Signup and view all the answers

What is the direction of the frictional force when an object is moving?

<p>Opposite to the object's motion (B)</p> Signup and view all the answers

What is the normal force exerted by a surface on an object?

<p>A force that prevents the object from penetrating the surface (B)</p> Signup and view all the answers

What is the result of friction between two surfaces in contact?

<p>A decrease in the object's motion (A)</p> Signup and view all the answers

What is an example of a contact force?

<p>Frictional force (D)</p> Signup and view all the answers

What is the relationship between friction and the normal force?

<p>Friction is directly proportional to the normal force (C)</p> Signup and view all the answers

What is the advantage of friction in vehicle safety?

<p>It prevents skidding (C)</p> Signup and view all the answers

What is the direction of the net force when an object is moving in a particular direction?

<p>In the same direction as the object's motion (C)</p> Signup and view all the answers

What is the purpose of representing forces using arrows?

<p>To indicate the direction and magnitude of the force (D)</p> Signup and view all the answers

What is a common characteristic of all three field forces?

<p>They act over a distance without physical contact (D)</p> Signup and view all the answers

What is the primary function of an electrolyte in an electric cell?

<p>To produce an electrically conducting solution (A)</p> Signup and view all the answers

What is the main difference between an electric cell and a mechanical generator?

<p>The presence of moving parts (D)</p> Signup and view all the answers

What is the role of the copper nail in the simple lemon battery experiment?

<p>To act as an electrode (C)</p> Signup and view all the answers

What is the purpose of a voltaic cell?

<p>To convert chemical energy into electrical energy (A)</p> Signup and view all the answers

What is the direction of the electrostatic force between two objects with opposite charges?

<p>Attractive (B)</p> Signup and view all the answers

What is the role of the lemon juice in the simple lemon battery experiment?

<p>To act as an electrolyte (C)</p> Signup and view all the answers

What is the primary difference between a battery and an electric cell?

<p>A battery is a group of two or more electric cells connected together (B)</p> Signup and view all the answers

What is the purpose of a salt bridge in a voltaic cell?

<p>To connect the oxidation and reduction half-cells (C)</p> Signup and view all the answers

What is the primary characteristic of magnetic forces?

<p>They can be attractive or repulsive (A)</p> Signup and view all the answers

Which of the following lighting systems has the highest efficiency of energy transfer?

<p>LED (D)</p> Signup and view all the answers

What is the primary factor that affects the resistance of a conductor?

<p>All of the above (D)</p> Signup and view all the answers

What happens to the resistance of a conductor when its length is increased?

<p>It increases (A)</p> Signup and view all the answers

What is the term for the energy that is wasted as heat in a system?

<p>Wasted Energy (D)</p> Signup and view all the answers

What is the effect of increasing the temperature of a conductor on its resistance?

<p>It increases (B)</p> Signup and view all the answers

What is the formula that relates resistance, resistivity, length, and cross-sectional area of a conductor?

<p>R = ρL/A (C)</p> Signup and view all the answers

What is the advantage of using thicker conductors?

<p>They have lower resistance (D)</p> Signup and view all the answers

What happens to the resistance of an incandescent bulb as it heats up?

<p>It increases (D)</p> Signup and view all the answers

What is the primary purpose of using a Sankey diagram?

<p>To compare the efficiency of different lighting systems (C)</p> Signup and view all the answers

What is the relationship between the length of a conductor and its resistance?

<p>They are directly proportional (D)</p> Signup and view all the answers

What is the primary function of a resistor in an electrical circuit?

<p>To control the current in the circuit (D)</p> Signup and view all the answers

What happens when electrons collide with the atoms of a conductor?

<p>Energy is transferred from the electrons to the atoms (A)</p> Signup and view all the answers

What is the primary difference between a rheostat and a fixed resistor?

<p>A rheostat has variable resistance, while a fixed resistor has fixed resistance (C)</p> Signup and view all the answers

Why are LEDs more efficient than incandescent bulbs?

<p>LEDs convert a higher percentage of electrical energy into light (A)</p> Signup and view all the answers

What is the purpose of a resistor in a circuit with an LED?

<p>To control the current flow through the LED (A)</p> Signup and view all the answers

What happens to the current in a circuit when the resistance is increased?

<p>The current decreases (D)</p> Signup and view all the answers

What is the term for the energy that is wasted as heat in a system?

<p>Wasted energy (D)</p> Signup and view all the answers

What is the direction of current flow through a diode?

<p>In one direction only (A)</p> Signup and view all the answers

What is the primary function of the U-tube filled with salt solution in the zinc-copper cell?

<p>To allow the flow of ions between the two solutions (D)</p> Signup and view all the answers

What is the primary purpose of using resistors in electrical circuits?

<p>To control the current in the circuit (A)</p> Signup and view all the answers

What happens to the zinc metal at the anode in the zinc-copper cell?

<p>It loses electrons and goes into the solution as zinc ions (D)</p> Signup and view all the answers

What is the relationship between electric current, voltage, and resistance described by?

<p>Ohm's Law (B)</p> Signup and view all the answers

What is the purpose of an ammeter or voltmeter in the zinc-copper cell?

<p>To measure the electric current or voltage (C)</p> Signup and view all the answers

What happens to the copper ions at the cathode in the zinc-copper cell?

<p>They gain electrons and become copper metal (D)</p> Signup and view all the answers

What is the term for the flow of electrons in an electrical conductor?

<p>Electric current (C)</p> Signup and view all the answers

What is the purpose of a resistor in an electrical circuit?

<p>To add resistance to the circuit (A)</p> Signup and view all the answers

What is the effect of increasing the resistance in an electrical circuit?

<p>The current decreases (D)</p> Signup and view all the answers

What is the term for a material that allows electric charge to flow through it easily?

<p>Conductor (B)</p> Signup and view all the answers

What is the result of the flow of electrons in an electrical conductor?

<p>Electric current is generated (D)</p> Signup and view all the answers

What is the advantage of connecting cells in parallel?

<p>Increased battery life and stable voltage (D)</p> Signup and view all the answers

What happens to the total resistance when resistors are added in parallel?

<p>It decreases (B)</p> Signup and view all the answers

What is the purpose of parallel circuits in homes?

<p>To allow multiple devices to operate independently (A)</p> Signup and view all the answers

What is the formula for calculating the total current in a parallel circuit?

<p>I_total = I1 + I2 + I3 (B)</p> Signup and view all the answers

What is the potential difference across each branch in a parallel circuit?

<p>The same as the potential difference across the battery (D)</p> Signup and view all the answers

What happens when the current divides in a parallel circuit?

<p>It is additive (A)</p> Signup and view all the answers

What is the risk of overloading parallel circuits?

<p>Fire or damage to the circuit (A)</p> Signup and view all the answers

What is the analogy used to describe the flow of current in a parallel circuit?

<p>A school hall with multiple exit doors (C)</p> Signup and view all the answers

What happens to the total voltage when cells are connected in series?

<p>It increases by the sum of the individual cell voltages (A)</p> Signup and view all the answers

What is the purpose of a voltmeter in a circuit?

<p>To measure the potential difference between two points (C)</p> Signup and view all the answers

What is the characteristic of a series circuit?

<p>It provides a single path for electric current (C)</p> Signup and view all the answers

What is the result of connecting resistors in series?

<p>The total resistance increases (C)</p> Signup and view all the answers

What is the purpose of an ammeter in a circuit?

<p>To measure the total current flowing through (C)</p> Signup and view all the answers

What is the characteristic of a parallel circuit?

<p>It provides multiple paths for electric current (B)</p> Signup and view all the answers

What happens to the current through each component in a series circuit?

<p>It remains the same (C)</p> Signup and view all the answers

What is the property of an ammeter?

<p>It has a very small resistance (B)</p> Signup and view all the answers

What is the result of connecting cells in series?

<p>The total voltage increases (A)</p> Signup and view all the answers

What is the purpose of measuring the potential difference across each component in a series circuit?

<p>To determine the voltage across each component (A)</p> Signup and view all the answers

What is the primary characteristic that distinguishes electrostatic force from gravitational force?

<p>Ability to be attractive or repulsive (C)</p> Signup and view all the answers

What is the primary difference between compression and tension forces?

<p>One occurs when an object is squashed, while the other occurs when an object is stretched. (D)</p> Signup and view all the answers

What is the role of the electrolyte in an electric cell?

<p>To produce an electrically conducting solution (D)</p> Signup and view all the answers

Which of the following is a common characteristic of both gravitational and magnetic forces?

<p>They both act over a distance. (C)</p> Signup and view all the answers

What is the purpose of the copper nail in the simple lemon battery experiment?

<p>To act as an electrode (D)</p> Signup and view all the answers

What is the primary difference between an electric cell and a mechanical generator?

<p>Type of energy conversion (B)</p> Signup and view all the answers

What is the primary difference between the gravitational force and the electrostatic force?

<p>One is always attractive, while the other can be either attractive or repulsive. (D)</p> Signup and view all the answers

What is the term used to describe the flow of electrons in an electrical conductor due to an electric potential difference?

<p>Electric current (C)</p> Signup and view all the answers

What is the role of the mass of objects in determining the gravitational force between them?

<p>The mass of the objects affects the magnitude of the force. (D)</p> Signup and view all the answers

What is the primary function of an electric cell?

<p>To convert chemical energy into electrical energy (A)</p> Signup and view all the answers

What is the term for the force that arises from the transfer of electrons between objects?

<p>Electrostatic force (B)</p> Signup and view all the answers

What is the purpose of the salt bridge in a voltaic cell?

<p>To connect the oxidation and reduction half-cells (A)</p> Signup and view all the answers

What is the primary difference between a bridge experiencing compression and a tennis ball experiencing compression?

<p>One is a result of weight, while the other is a result of external pressure. (D)</p> Signup and view all the answers

What is the primary characteristic that distinguishes magnetic force from gravitational force?

<p>Ability to be attractive or repulsive (D)</p> Signup and view all the answers

What is the term for the forces that act between objects without physical contact?

<p>Non-contact forces (D)</p> Signup and view all the answers

What is the primary characteristic of magnetic fields?

<p>Like poles repel, and opposite poles attract. (D)</p> Signup and view all the answers

What is the primary similarity between gravitational force, magnetic force, and electrostatic force?

<p>Non-contact nature (A)</p> Signup and view all the answers

What is the term used to describe a device that generates electricity from chemical reactions?

<p>Electric cell (B)</p> Signup and view all the answers

What is the formula for calculating the weight of an object on Earth?

<p>W = m × g (B)</p> Signup and view all the answers

What is the primary difference between the pillars of a bridge and the cables of a bridge?

<p>One experiences compression, while the other experiences tension. (A)</p> Signup and view all the answers

What is the primary advantage of connecting cells in parallel?

<p>Increased battery life and stable voltage (B)</p> Signup and view all the answers

What happens to the total resistance when resistors are added in parallel?

<p>It decreases (C)</p> Signup and view all the answers

What is the purpose of parallel circuits in homes?

<p>To allow multiple devices to operate independently (D)</p> Signup and view all the answers

What is the primary function of a resistor in an electrical circuit?

<p>To control the current flowing through the circuit (B)</p> Signup and view all the answers

What happens to the current when it enters separate branches in a parallel circuit?

<p>It divides (B)</p> Signup and view all the answers

What is the relationship between the potential difference across each branch and the potential difference across the battery in a parallel circuit?

<p>The potential difference across each branch is the same as the potential difference across the battery (B)</p> Signup and view all the answers

What is the primary factor that affects the efficiency of energy transfer in an LED lighting system?

<p>Type of material (C)</p> Signup and view all the answers

What happens when electrons collide with the atoms of a conductor?

<p>The conductor becomes warmer due to the transfer of kinetic energy (C)</p> Signup and view all the answers

What is the result of overloading a parallel circuit?

<p>The total resistance increases (A)</p> Signup and view all the answers

What is the primary characteristic of a rheostat?

<p>It is a variable resistor used to control current (C)</p> Signup and view all the answers

What is the net force on an object when multiple forces act on it, but they cancel each other out?

<p>A force of zero (D)</p> Signup and view all the answers

What is the relationship between the cross-sectional area of a conductor and its resistance?

<p>An increase in cross-sectional area results in a decrease in resistance (A)</p> Signup and view all the answers

What is the main difference between incandescent bulbs and LEDs?

<p>LEDs are more efficient and produce less heat (D)</p> Signup and view all the answers

What happens to the velocity of an object when a force is applied to it, causing it to accelerate?

<p>The velocity changes, and the direction also changes (B)</p> Signup and view all the answers

What is the effect of increasing the temperature of a conductor on its resistance?

<p>The resistance increases as the temperature increases (B)</p> Signup and view all the answers

Why does adding more devices in parallel not increase the overall resistance?

<p>Because the devices are connected in parallel (D)</p> Signup and view all the answers

What is the purpose of a resistor in a circuit with an LED?

<p>To protect the LED from high currents (D)</p> Signup and view all the answers

What is the purpose of the coiled tungsten wire in an incandescent bulb?

<p>To provide high resistance and heat up the filament (C)</p> Signup and view all the answers

Which of the following is an example of a force that can cause a change in shape?

<p>Pushing or pulling (A)</p> Signup and view all the answers

What is the analogy used to describe the flow of current in a parallel circuit?

<p>Students exiting a school hall (C)</p> Signup and view all the answers

What is the result of Newton's Third Law of Motion?

<p>An equal and opposite force is exerted by the second object (D)</p> Signup and view all the answers

What happens to the current in a circuit when the resistance is increased?

<p>The current decreases (A)</p> Signup and view all the answers

What is the term for the flow of electrons in an electrical conductor due to a potential difference?

<p>Electric current (D)</p> Signup and view all the answers

What is the unit of measurement for resistivity?

<p>Ohms per meter (Ω/m) (A)</p> Signup and view all the answers

What is the direction of the force exerted by the wall on you when you push against it?

<p>In the opposite direction of your push (D)</p> Signup and view all the answers

What is the primary function of a diode?

<p>To allow current to flow in only one direction (A)</p> Signup and view all the answers

What is the effect of increasing the length of a conductor on its resistance?

<p>The resistance increases as the length increases (C)</p> Signup and view all the answers

What is the term for the rate at which an object's velocity changes over time?

<p>Acceleration (B)</p> Signup and view all the answers

What is the formula for calculating the resistance of a conductor?

<p>R = ρL/A (B)</p> Signup and view all the answers

What is the term for the energy wasted as heat in a system?

<p>Wasted energy (A)</p> Signup and view all the answers

What is the result of unbalanced forces acting on an object?

<p>The object will accelerate in the direction of the net force (C)</p> Signup and view all the answers

What is the main difference between an incandescent bulb and an LED?

<p>The efficiency of energy transfer (A)</p> Signup and view all the answers

What is the unit of measurement for force?

<p>Newton (B)</p> Signup and view all the answers

What happens to the light emitted by an LED when the resistance in the circuit is increased?

<p>The light becomes dimmer (A)</p> Signup and view all the answers

What is the term for the energy that is wasted as heat in a system?

<p>Thermal energy (D)</p> Signup and view all the answers

What is the primary function of the copper plate in the zinc-copper cell?

<p>To allow the flow of electrons from the zinc plate (D)</p> Signup and view all the answers

What is the result of the chemical reaction occurring at the zinc electrode in the zinc-copper cell?

<p>Zinc metal loses electrons (B)</p> Signup and view all the answers

What is the purpose of the U-tube filled with salt solution in the zinc-copper cell?

<p>To allow the flow of ions between the two solutions (C)</p> Signup and view all the answers

What is the definition of a resistor in electrical circuits?

<p>An electrical component that adds resistance to a circuit (A)</p> Signup and view all the answers

What is the relationship between current, voltage, and resistance described by?

<p>Ohm's Law (C)</p> Signup and view all the answers

What is the result of the movement of electrons in a conductor?

<p>Electric current flows in the same direction (B)</p> Signup and view all the answers

What is the primary characteristic of a conductor?

<p>It has low resistance (D)</p> Signup and view all the answers

What is the purpose of the ammeter or voltmeter in the zinc-copper cell?

<p>To measure the current of the cell (D)</p> Signup and view all the answers

What is the flow of electrons in an electrical conductor due to?

<p>The energy source, such as a battery (C)</p> Signup and view all the answers

Why does resistance occur in an electrical circuit?

<p>Because of the collisions between electrons and the atoms of the conductor (C)</p> Signup and view all the answers

What happens to the total resistance when resistors are added in series?

<p>It increases (B)</p> Signup and view all the answers

What is the purpose of a voltmeter in a circuit?

<p>To measure the potential difference between two points in the circuit (D)</p> Signup and view all the answers

What is the characteristic of a parallel circuit?

<p>It provides more than one path for electric current to move through the circuit (A)</p> Signup and view all the answers

What happens to the voltage across each resistor when cells are connected in series?

<p>It divides equally (C)</p> Signup and view all the answers

What is the effect of temperature on the resistance of conductors?

<p>It increases the resistance (A)</p> Signup and view all the answers

What is the purpose of an ammeter in a circuit?

<p>To measure the current flowing through the circuit (D)</p> Signup and view all the answers

What is the characteristic of a series circuit?

<p>It provides only one path for electric current to move through the circuit (B)</p> Signup and view all the answers

What happens to the total current when resistors are added in series?

<p>It decreases (C)</p> Signup and view all the answers

Why do resistors have a small resistance when used as an ammeter?

<p>So they don't affect the current they are measuring (A)</p> Signup and view all the answers

What happens to the total voltage when cells are connected in parallel?

<p>It remains the same (A)</p> Signup and view all the answers

What is the main purpose of a spring balance in measuring forces?

<p>To measure the magnitude of a force (D)</p> Signup and view all the answers

Which of the following is an example of a non-contact force?

<p>Gravitational force (B)</p> Signup and view all the answers

What is the direction of the frictional force when an object is moving?

<p>In the opposite direction to the motion (B)</p> Signup and view all the answers

What is the normal force equal to on a flat, level surface?

<p>The normal force equals the object's weight but in the opposite direction (B)</p> Signup and view all the answers

What is the relationship between friction and normal force?

<p>Friction is proportional to the normal force (D)</p> Signup and view all the answers

What is the advantage of friction in vehicle safety?

<p>It prevents skidding (A)</p> Signup and view all the answers

What type of force occurs when an object is being pulled by forces acting from opposite ends?

<p>Tension force (B)</p> Signup and view all the answers

What is the net force calculated as in the example of pushing a go-cart?

<p>The difference between the forces pushing it forward and friction (B)</p> Signup and view all the answers

What is the direction of the normal force on a flat, level surface?

<p>Upward (B)</p> Signup and view all the answers

What is the advantage of friction in movement?

<p>It allows us to walk without slipping (A)</p> Signup and view all the answers

What is the primary fuel used in a nuclear power station due to its ability to undergo fission?

<p>Uranium (D)</p> Signup and view all the answers

What is the process of combining two light atomic nuclei to form a heavier nucleus, releasing energy?

<p>Nuclear Fusion (B)</p> Signup and view all the answers

What is the primary purpose of control rods in a nuclear reactor?

<p>To regulate the fission process (C)</p> Signup and view all the answers

What is the term for the energy produced from controlled nuclear reactions?

<p>Nuclear Power (A)</p> Signup and view all the answers

What is the purpose of the cooling system in a nuclear power plant?

<p>To ensure the reactor and other components remain at safe operating temperatures (D)</p> Signup and view all the answers

What is the advantage of nuclear power generation in terms of greenhouse gas emissions?

<p>Minimal greenhouse gas emissions (A)</p> Signup and view all the answers

What is the purpose of radiation containment in a nuclear power plant?

<p>To prevent radiation leakage (C)</p> Signup and view all the answers

What is the term for the process of splitting a heavy atomic nucleus into two smaller nuclei, releasing energy?

<p>Nuclear Fission (A)</p> Signup and view all the answers

What is the location of the Koeberg Nuclear Power Station in South Africa?

<p>Cape Town (A)</p> Signup and view all the answers

What is the primary difference between nuclear power and alternative energy sources?

<p>Renewability (C)</p> Signup and view all the answers

What is the primary purpose of earthing in electrical appliances?

<p>To prevent electric shocks by connecting the metal casing to the ground (C)</p> Signup and view all the answers

What happens when a live wire touches the metal casing of an electrical appliance with proper earthing?

<p>The current will flow through the earth wire to the ground, preventing an electric shock (B)</p> Signup and view all the answers

What is the function of a fuse in an electrical circuit?

<p>To melt and break the circuit when current exceeds a safe level (D)</p> Signup and view all the answers

What is the primary purpose of a short circuit?

<p>To create an unintended low-resistance path, causing a surge in current (B)</p> Signup and view all the answers

What is the function of an earth leakage circuit breaker?

<p>To detect any leakage of current to the earth wire and immediately shut off the power (B)</p> Signup and view all the answers

What is the primary advantage of nuclear power plants compared to some renewable energy sources?

<p>They can operate continuously and are not dependent on weather conditions (B)</p> Signup and view all the answers

What is the typical location of an earth leakage circuit breaker?

<p>On the electrical distribution board in homes (A)</p> Signup and view all the answers

What is the term for a network of interacting components that work together to provide electricity across a country?

<p>National Electricity Grid (A)</p> Signup and view all the answers

What is the primary cause of overloading in parallel circuits?

<p>Too many devices connected to the circuit (B)</p> Signup and view all the answers

What is the primary consequence of overloading in parallel circuits?

<p>Excessive heat build-up, potentially leading to electrical fires (B)</p> Signup and view all the answers

What is the purpose of step-up transformers in the national electricity grid?

<p>To increase the voltage of electricity for efficient transmission (B)</p> Signup and view all the answers

What is the effect of a power surge on sensitive electronic devices and circuits?

<p>It can cause damage to them (D)</p> Signup and view all the answers

What is the term for a device that changes the voltage of an electric current?

<p>Transformer (C)</p> Signup and view all the answers

What is the primary safety risk associated with nuclear power plants?

<p>Accidents and radiation leaks (B)</p> Signup and view all the answers

What is the purpose of pylons in the national electricity grid?

<p>To support transmission lines and keep them elevated and secure (C)</p> Signup and view all the answers

What happens to the voltage of electricity during transmission in the national electricity grid?

<p>It is stepped up and then stepped down (B)</p> Signup and view all the answers

What is the purpose of grid monitoring in the national electricity grid?

<p>To detect and prevent power surges and overloads (B)</p> Signup and view all the answers

What is the term for a sudden increase in voltage within an electrical circuit?

<p>Power Surge (C)</p> Signup and view all the answers

What is the primary function of step-up transformers in a power grid?

<p>To increase voltage and decrease current before transmission (B)</p> Signup and view all the answers

What is the unit of measurement for the energy consumed by an appliance?

<p>Kilowatt-hour (kWh) (D)</p> Signup and view all the answers

What is the purpose of a tiered tariff system used by Eskom?

<p>To charge consumers a higher rate for higher usage (A)</p> Signup and view all the answers

What is the formula for calculating energy consumption in joules?

<p>Energy = Power × Time (B)</p> Signup and view all the answers

What is the purpose of step-down transformers in a power grid?

<p>To decrease voltage and increase current before distribution (A)</p> Signup and view all the answers

What is the unit of measurement for power?

<p>Watt (C)</p> Signup and view all the answers

What is the term for the price schedule or rate for services provided by Eskom?

<p>Tariff (A)</p> Signup and view all the answers

What is the purpose of calculating energy consumption in kWh?

<p>To find the cost of electricity consumption (B)</p> Signup and view all the answers

What is the primary method of generating electricity in power stations?

<p>Converting different forms of energy into electrical energy (C)</p> Signup and view all the answers

What is the purpose of the turbine in a coal-powered power station?

<p>To convert mechanical energy into electrical energy (B)</p> Signup and view all the answers

What is the primary reason behind illegal connections in areas where electricity is not accessible?

<p>Lack of access to legal electricity connections (B)</p> Signup and view all the answers

What is the environmental disadvantage of relying on coal for electricity generation?

<p>It contributes to environmental pollution, greenhouse gas emissions, and climate change (B)</p> Signup and view all the answers

What is the consequence of overloaded power grids due to illegal connections?

<p>Frequent power outages and disruptions (B)</p> Signup and view all the answers

What is the process of generating electricity from hydroelectric power?

<p>Using the potential energy of stored water to generate electricity (D)</p> Signup and view all the answers

What is the primary function of a lightning rod?

<p>To channel lightning strikes away from buildings (C)</p> Signup and view all the answers

What is the advantage of using solar power for electricity generation?

<p>It is abundant and renewable, and has no emissions during operation (B)</p> Signup and view all the answers

What is the result of exposed wires and poor-quality connections in illegal connections?

<p>Sparks that can ignite nearby flammable materials (C)</p> Signup and view all the answers

What is the purpose of a generator in a power station?

<p>To convert mechanical energy into electrical energy (C)</p> Signup and view all the answers

What is the advantage of using wind power for electricity generation?

<p>It is renewable, has low operational costs, and has no emissions during operation (B)</p> Signup and view all the answers

What is the purpose of education campaigns to address illegal connections?

<p>To educate people on the risks of illegal connections and the benefits of legal connections (B)</p> Signup and view all the answers

What is the consequence of individuals resorting to illegal connections to avoid paying for electricity?

<p>Electricity theft, affecting the revenue of utility companies (C)</p> Signup and view all the answers

What is the process of generating electricity using a portable generator?

<p>Burning fuel such as petrol or diesel to generate electricity (B)</p> Signup and view all the answers

What is the purpose of pulverization in a coal-powered power station?

<p>To crush large chunks of coal into a fine powder (B)</p> Signup and view all the answers

What is the primary motivation behind some individuals profiting from illegal connections?

<p>Financial gain (B)</p> Signup and view all the answers

What is the environmental advantage of using alternative energy sources such as hydroelectric power?

<p>It is renewable, and has less pollution and emissions compared to coal (A)</p> Signup and view all the answers

What is the consequence of insecure and exposed electrical connections in illegal connections?

<p>Severe risk of electrocution (C)</p> Signup and view all the answers

What is the purpose of strengthening regulations and enforcement against illegal connections?

<p>To deter illegal connections and promote safe and legal electricity access (D)</p> Signup and view all the answers

What is the primary characteristic of illegal connections?

<p>Direct connection to the national grid without proper authorization (D)</p> Signup and view all the answers

What is the primary purpose of the environmental levy in the tariff structure?

<p>To generate revenue for the government (A)</p> Signup and view all the answers

What is the correct formula for calculating the cost of using an electrical appliance?

<p>cost = power rating x time x price (B)</p> Signup and view all the answers

What is the unit of measurement for electrical power?

<p>Watts (W) (D)</p> Signup and view all the answers

What is the purpose of conducting a household energy survey?

<p>To identify areas for energy efficiency improvement (B)</p> Signup and view all the answers

What is the characteristic of energy-efficient appliances?

<p>They consume less energy than traditional appliances (A)</p> Signup and view all the answers

What is the term for the rate at which electrical energy is supplied or consumed by a device?

<p>Electrical power (D)</p> Signup and view all the answers

What is the correct formula for calculating electrical power?

<p>power = energy / time (D)</p> Signup and view all the answers

What is the purpose of the label or stamp on an electrical appliance?

<p>To provide the appliance's power rating (B)</p> Signup and view all the answers

What is the unit of measurement for energy consumption?

<p>Kilowatt-hours (kWh) (A)</p> Signup and view all the answers

What is the result of using energy-efficient appliances?

<p>Decreased energy consumption (A)</p> Signup and view all the answers

What is the primary motivation behind illegal electricity connections in certain areas?

<p>Lack of access to legal electricity supply (C)</p> Signup and view all the answers

What is a common risk associated with illegal electricity connections?

<p>Both A and B (C)</p> Signup and view all the answers

What is a likely consequence of illegal electricity connections on the power grid?

<p>Frequent power outages and disruptions (D)</p> Signup and view all the answers

What is a potential solution to address illegal electricity connections?

<p>Implementing programs to extend legal access to underserved areas (A)</p> Signup and view all the answers

What is the main reason why individuals might choose to use illegal electricity connections despite having legal access?

<p>To avoid paying for electricity (A)</p> Signup and view all the answers

What is a common characteristic of illegal electricity connections?

<p>Exposed wires and insecure connections (C)</p> Signup and view all the answers

What is a consequence of electricity theft on utility companies?

<p>Reduced investment in infrastructure improvements (A)</p> Signup and view all the answers

What is a key aspect of discussing the risks of illegal electricity connections?

<p>Examining the setup of an illegal connection (D)</p> Signup and view all the answers

What is a potential solution to address the safety hazards associated with illegal electricity connections?

<p>Implementing education campaigns to raise awareness about the risks (A)</p> Signup and view all the answers

What is the primary purpose of earthing in electrical appliances?

<p>To prevent electric shocks by connecting metal parts to the ground (B)</p> Signup and view all the answers

What happens when a live wire accidentally touches the metal casing of an appliance?

<p>The current flows through the earth wire, creating a short circuit (C)</p> Signup and view all the answers

What is the purpose of strengthening regulations and enforcement against illegal connections?

<p>To deter illegal connections and promote legal access (B)</p> Signup and view all the answers

What is the function of a fuse in an electrical circuit?

<p>To melt and break the circuit when the current exceeds a safe level (B)</p> Signup and view all the answers

What is the primary fuel used in nuclear power stations?

<p>Uranium (C)</p> Signup and view all the answers

What is a short circuit?

<p>An unintended low-resistance path created in a circuit, causing a surge in current (D)</p> Signup and view all the answers

What is the process of splitting a heavy atomic nucleus into two smaller nuclei, releasing energy?

<p>Nuclear Fission (D)</p> Signup and view all the answers

What is the purpose of an earth leakage circuit breaker?

<p>To detect any leakage of current to the earth wire and immediately shut off the power (A)</p> Signup and view all the answers

What is the purpose of control rods in a nuclear reactor?

<p>To regulate the fission process by absorbing excess neutrons (B)</p> Signup and view all the answers

Where are earth leakage circuit breakers typically located?

<p>On the electrical distribution board in homes (D)</p> Signup and view all the answers

What is the main difference between a fuse and a circuit breaker?

<p>A fuse breaks the circuit when the current exceeds a safe level, while a circuit breaker can be reset after a fault (A)</p> Signup and view all the answers

What is the advantage of nuclear power generation in terms of climate change?

<p>Low greenhouse gas emissions (C)</p> Signup and view all the answers

Why is it important to manage the load on each circuit?

<p>To prevent overheating and electrical fires (C)</p> Signup and view all the answers

What is the term for the energy produced from controlled nuclear reactions?

<p>Nuclear Power (D)</p> Signup and view all the answers

What is the purpose of the cooling system in a nuclear power station?

<p>To ensure the reactor and other components remain at safe operating temperatures (D)</p> Signup and view all the answers

What is the term for the process of combining two light atomic nuclei to form a heavier nucleus, releasing energy?

<p>Nuclear Fusion (A)</p> Signup and view all the answers

What is the location of the Koeberg Nuclear Power Station?

<p>Cape Town, South Africa (C)</p> Signup and view all the answers

What is the term for the emission of radiation as a result of the decay of atomic nuclei?

<p>Radioactive Decay (D)</p> Signup and view all the answers

What is the purpose of radiation containment in a nuclear power station?

<p>To prevent radiation leakage (C)</p> Signup and view all the answers

What is the primary method of generating electricity in South Africa?

<p>Coal (C)</p> Signup and view all the answers

What is the purpose of the turbine in a coal-powered power station?

<p>To push the blades of a generator (B)</p> Signup and view all the answers

What is a disadvantage of using coal as an energy source?

<p>It contributes to environmental pollution (A)</p> Signup and view all the answers

What is the process of generating electricity in a hydroelectric power plant?

<p>Using the potential energy of stored water to generate electricity (C)</p> Signup and view all the answers

What is an advantage of using wind power as an energy source?

<p>It is renewable and has low operational costs (B)</p> Signup and view all the answers

What is the purpose of a generator in a power station?

<p>To convert mechanical energy into electrical energy (B)</p> Signup and view all the answers

What is an alternative energy source used to generate electricity?

<p>All of the above (D)</p> Signup and view all the answers

What is the purpose of a portable generator?

<p>To generate electricity during power outages (D)</p> Signup and view all the answers

What is the result of the combustion process in a coal-powered power station?

<p>The generation of heat (A)</p> Signup and view all the answers

What is the term for energy sources that are not derived from fossil fuels?

<p>Alternative energy (C)</p> Signup and view all the answers

What is the primary function of step-up transformers in the electrical grid?

<p>To increase voltage and decrease current before transmission (B)</p> Signup and view all the answers

What is the purpose of a tiered tariff system in electricity pricing?

<p>To penalize high-energy consumers with higher rates (D)</p> Signup and view all the answers

What is the unit of measurement for energy consumption in household appliances?

<p>Kilowatt-hours (kWh) (C)</p> Signup and view all the answers

What is the formula for calculating energy consumption in kWh?

<p>Energy (kWh) = Power (W) x Time (h) (C)</p> Signup and view all the answers

What is the term for the amount of electrical energy used by an appliance or device?

<p>Power Consumption (A)</p> Signup and view all the answers

What is the primary electricity supplier in South Africa?

<p>Eskom (D)</p> Signup and view all the answers

What is the purpose of step-down transformers in the electrical grid?

<p>To decrease voltage and increase current before distribution (A)</p> Signup and view all the answers

What is the unit of measurement for the total amount of visible light emitted by a source?

<p>Lumens (lm) (B)</p> Signup and view all the answers

What is a major advantage of nuclear power plants over some renewable energy sources?

<p>They can operate continuously and are not dependent on weather conditions (D)</p> Signup and view all the answers

What is a major concern with nuclear power?

<p>The risk of accidents and radiation leaks (C)</p> Signup and view all the answers

What is the purpose of a transformer in the national electricity grid?

<p>To change the voltage of an electric current (C)</p> Signup and view all the answers

What is the primary function of pylons in the national electricity grid?

<p>To support overhead power lines (D)</p> Signup and view all the answers

What is the rate at which electrical energy is supplied or consumed by a device?

<p>Electrical power (C)</p> Signup and view all the answers

What is the result of a power surge in the national electricity grid?

<p>An increase in voltage (A)</p> Signup and view all the answers

What is the purpose of a surge protector in the national electricity grid?

<p>To absorb excess voltage and prevent damage (C)</p> Signup and view all the answers

What is the formula to calculate the cost of operating an appliance?

<p>cost = power rating x time x price (D)</p> Signup and view all the answers

What is the unit of measurement for power?

<p>Watt (W) (C)</p> Signup and view all the answers

What is the main component of a coal-powered power station that generates electricity?

<p>Generator (D)</p> Signup and view all the answers

What is the primary purpose of the step-up transformer in a power station?

<p>To increase the voltage of an electric current (C)</p> Signup and view all the answers

What is the purpose of a household energy survey?

<p>To understand the household's energy consumption (D)</p> Signup and view all the answers

What is the purpose of the national electricity grid?

<p>To distribute electricity to homes and businesses (A)</p> Signup and view all the answers

What is the environmental levy for Block 2 energy consumption?

<p>2.28 c/kWh (B)</p> Signup and view all the answers

What is the main function of the grid monitoring system?

<p>To cut off the power supply during a power surge (C)</p> Signup and view all the answers

What is the energy charge for Block 3 energy consumption?

<p>124.74 c/kWh (B)</p> Signup and view all the answers

What is the total cost of energy consumption for a household that uses 252 kWh in a month?

<p>R207.59 (C)</p> Signup and view all the answers

What is the power rating of a 1500 W microwave?

<p>1.5 kW (C)</p> Signup and view all the answers

What is the purpose of looking for a label or stamp on an appliance?

<p>To determine the power rating (B)</p> Signup and view all the answers

What is the energy consumption block for a household that uses more than 600 kWh in a month?

<p>Block 4 (D)</p> Signup and view all the answers

What is the primary purpose of a lightning rod?

<p>To safely channel lightning strikes away from buildings (D)</p> Signup and view all the answers

What is a common motivation behind illegal electricity connections?

<p>To avoid paying for electricity (D)</p> Signup and view all the answers

What is a risk associated with illegal electricity connections?

<p>Fire risk and electrocution (A)</p> Signup and view all the answers

What is a consequence of illegal electricity connections?

<p>Legal consequences, including fines and imprisonment (D)</p> Signup and view all the answers

What is the main purpose of earthing in electrical appliances?

<p>To prevent electric shocks by connecting the metal casing to the ground (A)</p> Signup and view all the answers

What is a solution to address illegal electricity connections?

<p>Implement programs to extend legal electricity access (B)</p> Signup and view all the answers

What occurs when a live wire touches the metal casing of an electrical appliance?

<p>A short circuit is created, protecting the user from electric shock (A)</p> Signup and view all the answers

What is the function of a fuse in an electrical circuit?

<p>To break the circuit when the current exceeds a safe level (D)</p> Signup and view all the answers

Why do some areas resort to illegal electricity connections?

<p>Due to lack of access to electricity (C)</p> Signup and view all the answers

What can happen due to overloading from illegal connections?

<p>Power outages and service disruptions (D)</p> Signup and view all the answers

What is the primary function of an earth leakage circuit breaker?

<p>To detect and prevent leakage of current to the earth wire (C)</p> Signup and view all the answers

What is a risk of exposed wires and connections in illegal electricity connections?

<p>Severe risk of electric shock and electrocution (D)</p> Signup and view all the answers

What happens when a short circuit occurs in an electrical circuit?

<p>A surge in current causes damage to appliances and overheating (B)</p> Signup and view all the answers

What can education campaigns achieve in addressing illegal electricity connections?

<p>Reduce the number of illegal connections (A)</p> Signup and view all the answers

What is the purpose of the neutral wire in an electrical circuit?

<p>To carry current away from the appliance (A)</p> Signup and view all the answers

What is a result of electricity theft on utility companies?

<p>Higher costs for legitimate consumers (B)</p> Signup and view all the answers

What is the primary cause of electrical fires in parallel circuits?

<p>Overloading of the circuit (A)</p> Signup and view all the answers

What is the purpose of managing the load on each circuit?

<p>To prevent overheating and electrical fires (C)</p> Signup and view all the answers

What is the primary fuel used in a nuclear power station?

<p>Uranium (C)</p> Signup and view all the answers

What is the process of splitting a heavy atomic nucleus into two smaller nuclei, releasing energy?

<p>Nuclear Fission (B)</p> Signup and view all the answers

What is the primary method of generating electricity in South Africa?

<p>Coal (B)</p> Signup and view all the answers

What is the purpose of control rods in a nuclear reactor?

<p>To regulate the fission process (A)</p> Signup and view all the answers

What is the role of a turbine in a coal-powered power station?

<p>To convert mechanical energy into electrical energy (B)</p> Signup and view all the answers

What is the advantage of nuclear power generation compared to fossil fuels?

<p>Lower greenhouse gas emissions (A)</p> Signup and view all the answers

What is the function of a generator in a power station?

<p>To convert mechanical energy into electrical energy (A)</p> Signup and view all the answers

What is the process of combining two light atomic nuclei to form a heavier nucleus, releasing energy?

<p>Nuclear Fusion (B)</p> Signup and view all the answers

What is the environmental impact of relying on coal for electricity generation?

<p>It leads to habitat destruction and health issues (D)</p> Signup and view all the answers

What is the process of generating electricity from falling water?

<p>Hydroelectric power (D)</p> Signup and view all the answers

What is the term for the energy produced from controlled nuclear reactions?

<p>Nuclear Power (B)</p> Signup and view all the answers

What is the location of the Koeberg Power Station in South Africa?

<p>Cape Town (B)</p> Signup and view all the answers

What is the advantage of using wind power for electricity generation?

<p>It is a renewable energy source with low operational costs (B)</p> Signup and view all the answers

What is the process of generating electricity from sunlight?

<p>Photovoltaic cells (C)</p> Signup and view all the answers

What is the purpose of the cooling system in a nuclear power station?

<p>To ensure the reactor and other components remain at safe operating temperatures (A)</p> Signup and view all the answers

What is the purpose of a portable generator?

<p>To provide power during grid outages (D)</p> Signup and view all the answers

What is the result of radioactive decay?

<p>The unstable nucleus transforms into a different element (C)</p> Signup and view all the answers

What is an alternative energy source that uses heat from the Earth's interior to generate electricity?

<p>Geothermal energy (D)</p> Signup and view all the answers

What is the term for emitting radiation as a result of the decay of atomic nuclei?

<p>Radioactive (C)</p> Signup and view all the answers

What is the primary characteristic of a power station?

<p>It is a facility for the generation of electrical power (C)</p> Signup and view all the answers

What is the primary function of Step-Up Transformers in the grid?

<p>To increase voltage and decrease current before transmission (D)</p> Signup and view all the answers

What is the unit of energy consumption commonly used for monthly energy bills?

<p>Kilowatt-hours (kWh) (C)</p> Signup and view all the answers

What is the purpose of Eskom's tiered tariff system?

<p>To charge higher rates for higher usage levels (A)</p> Signup and view all the answers

What is the formula to calculate energy consumption?

<p>energy = power × time (D)</p> Signup and view all the answers

What is the primary electricity supplier in South Africa?

<p>Eskom (C)</p> Signup and view all the answers

What is the purpose of a Step-Down Transformer?

<p>To decrease voltage and increase current before distribution to homes and businesses (C)</p> Signup and view all the answers

What is the unit of measurement for power?

<p>Watts (W) (C)</p> Signup and view all the answers

What is the purpose of calculating energy consumption?

<p>To determine the cost of electrical power (C)</p> Signup and view all the answers

What is the unit of power equal to one joule of energy per second?

<p>Watt (W) (C)</p> Signup and view all the answers

What is the rate at which electrical energy is supplied or consumed by a device?

<p>Electrical Power (D)</p> Signup and view all the answers

What is the formula to calculate the cost of operating an appliance?

<p>cost = power rating × time × price (C)</p> Signup and view all the answers

What is the purpose of conducting a household energy survey?

<p>To understand the household's energy consumption pattern (A)</p> Signup and view all the answers

What is the term for forces that act between objects without physical contact?

<p>Non-Contact Forces (C)</p> Signup and view all the answers

What is the block tariff structure used for?

<p>To calculate the cost of energy consumption (C)</p> Signup and view all the answers

What is the unit of measurement for energy?

<p>Joule (J) (B)</p> Signup and view all the answers

What does the power rating of an appliance indicate?

<p>The rate at which the appliance consumes energy (B)</p> Signup and view all the answers

What is the purpose of looking for a label or stamp on an appliance?

<p>To identify the power rating of the appliance (D)</p> Signup and view all the answers

What is the term for the rate at which energy is being used?

<p>Electrical Power (D)</p> Signup and view all the answers

What is a major advantage of nuclear power plants?

<p>They can operate continuously. (B)</p> Signup and view all the answers

What is a major disadvantage of nuclear power plants?

<p>They have high initial costs. (B)</p> Signup and view all the answers

What is the main purpose of a transformer in the national electricity grid?

<p>To change the voltage of an electric current. (D)</p> Signup and view all the answers

What is the purpose of pylons in the national electricity grid?

<p>To support overhead power lines. (B)</p> Signup and view all the answers

What is a power surge?

<p>A sudden increase in voltage. (D)</p> Signup and view all the answers

What is the purpose of a surge protector?

<p>To safeguard appliances from power surges. (A)</p> Signup and view all the answers

What is the main purpose of the national electricity grid?

<p>To ensure the delivery of electricity from power stations to consumers. (C)</p> Signup and view all the answers

What is the purpose of step-up transformers in the national electricity grid?

<p>To increase the voltage of an electric current. (D)</p> Signup and view all the answers

What happens to the voltage of an electric current when it is transmitted over long distances?

<p>It decreases. (D)</p> Signup and view all the answers

What is the purpose of the diagram of a coal-powered power station connected to the grid?

<p>To describe how electricity is generated from coal and transmitted to the grid. (A)</p> Signup and view all the answers

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