Physics Notes on Current (PDF)

ER How do you get light in your room?  SKILLS By the end of the lesson, I would be able to: - define current electricity - explain electrical circuit and symbols of circuit components.  SUCCESS CRITERIA Series circuit is a connection of electrical components in which...

ER How do you get light in your room?  SKILLS By the end of the lesson, I would be able to: - define current electricity - explain electrical circuit and symbols of circuit components.  SUCCESS CRITERIA Series circuit is a connection of electrical components in which the battery flows in one direction only Parallel circuit is a connection of electrical components in which the current flows through different directions  CURRENT ELECTRICITY Current electricity is the flow of negative charges or electrons. Current is measured  Conventional current is the flow of positive charges (protons)  https://phet.colorado.edu/sims/html/circ uit-construction-kit-dc-virtual-lab/latest/ circuit-construction-kit-dc-virtual-lab_al l.html  ELECTRICAL CIRCUIT Electrical circuit is the path that electrical charges flow through to get to other components CIRCUIT COMPONENTS AND THEIR SYMBOLS DRY CELL BATTER Y  BULB OR LAMP Ammeter: it is used to measure current. An ammeter is connected in series (along) in a circuit A CHECKPOINT QUESTION, 2018 SUMMER P2 This is a complete electrical (a) Add an ammeter to circuit. the circuit diagram to show how you would measure the current flowing through lamp 2. VOLTMETER: it is used to measure voltage or potential difference A voltmeter is connect parallel (across) to a component to measure the voltage or potential difference A CHECKPOINT QUESTION, 2018 SUMMER P2 This is a complete electrical (b) Add a voltmeter circuit. to the circuit diagram to show how you would measure the voltage across lamp2. Look at the reading on the voltmeter. It is connected to the 0 – 4V scale. THE READING ON THIS VOLTMETER IS V The reading on this voltmeter is………. V RESISTOR: it impedes or obstruct the flow of current. It is use to measure resistance in a circuit.  Resistance is measured in ohm (Ω )  TYPES OF RESISTORS 1. VARIABLE RESISTOR (RHEOSTAT) 2. FIXED RESISTOR CONNECTING WIRE  KEY (SWITCH) it is used to switch on or off the circuit.  LED (LIGHT EMITTING DIODE): It glows when a voltage is applied A BUZZER: is an audio signaling device.  STARTER Draw the symbol of a buzzer  SERIES CIRCUIT CONNECTION Series circuit is a connection of electrical components in which the current flows in one direction only. All the components receive the same amount of current. CONNECTING BULBS IN SERIES  EXERCISE 1. Draw a circuit consisting of a cell, a switch, connecting wires, and four bulbs connected in series ANSWER CONNECTING CELLS IN SERIES  EXERCISE 2. Draw a circuit consisting of a lamp, a switch, connecting wires, and four cells connected in series  Parallel circuit is a connection of electrical components in which the current flows through different directions. In parallel connection, the components receive different amount of current. CONNECTING CELLS IN PARALLEL  OHM’S LAW It states that the current through a conductor is directly proportional to the potential difference across the conductor at constant temperature.