Science Quiz: The Solar System and Ecosystems

The time it takes a planet to complete one full rotation on its axis.

The time it takes a planet to complete one full orbit around the Sun.

A large ball of hot gas that produces its own light and heat through nuclear fusion in its core. They are primarily composed of hydrogen and helium.

A celestial body that orbits a star. They do not produce their own light and heat. They can be made of rock, gas, or a combination of both.

The hottest stars are blue, while the coolest stars are red.

Non-living factors in an ecosystem, like temperature, sunlight, water, and soil.

The variety of life within an ecosystem or on Earth.

The part of Earth where life exists, including all living organisms and their environments.

All the populations of different species that live and interact in a particular area.

The study of how living organisms interact with each other and their environment.

The process by which plants use sunlight, water, and carbon dioxide to create their own food.

The process by which organisms break down food to release energy.

The maximum number of individuals of a species that an ecosystem can support.

The difference between static electricity and current electricity is that static electricity is a buildup of electric charges on the surface of an object, while current electricity is the flow of electric charges through a conductor. Static electricity usually occurs when two objects are rubbed together and electrons are transferred between them. The charges build up on the surface of the objects. Current electricity is the flow of electrons through a conductor. This flow is caused by a potential difference (voltage) between two points in a circuit.

The electrostatic series is a list of materials that are ordered by their tendency to gain or lose electrons. When two different materials rub against each other, the material higher on the list will lose electrons and become positively charged, while the material lower on the list will gain electrons and become negatively charged. For example, if glass rubs against silk, glass will lose electrons and become positively charged, while silk will gain electrons and become negatively charged.

Charging by friction is a method of charging an object by rubbing it against another object. When two different materials are rubbed together, electrons are transferred from one object to another. The object that loses electrons becomes positively charged, and the object that gains electrons becomes negatively charged.

The law of electric charges states that like charges repel each other, while unlike charges attract each other. You can see an example when you rub a balloon on your hair and it sticks to the wall; the opposite charges attract.

A neutral object has an equal number of protons and electrons. A positively charged object has more protons than electrons, while a negatively charged object has more electrons than protons.

Current (I) is the rate of flow of electrical charge through a conductor. It is measured in amperes (A). Voltage (V) is the potential difference between two points in an electric circuit. It is measured in volts. Resistance (R) is the measure of how much a material opposes the flow of current. It is measured in ohms (Ω).

A series circuit is one where all the components are connected in a single loop, so the current flows through each component in turn. If one component is broken, the circuit is broken, and no current will flow. A parallel circuit has multiple paths for the current to flow. If one path is broken, the current can still flow through the other paths.

A conductor is a material that allows electric current to flow easily through it. Examples of conductors include metals like copper and silver. An insulator is a material that resists the flow of electric current. Examples of insulators include rubber, glass, and plastic. The flow of electricity is related to the materials' electrons and how easily they can move.

The proportion of electrical energy converted into useful energy. In the case of the lightbulb, only 10% of the electrical energy is converted to light energy. The rest is lost as heat energy due to inefficiency.

Increasing resistance in a circuit with constant voltage will decrease the electric current. We can see this with Ohm's Law: I = V / R

As R increases, the current (I) decreases.

Homes are wired in parallel because it allows all appliances to be used at the same time, with the same voltage across each appliance. If they were in series, one faulty appliance would shut off the entire circuit.

The voltage across the circuit can be calculated using Ohm's Law: V = I * R

Therefore, the voltage across the circuit would be V = (2 A) * (0.5 ohms) = 1 volt.

Electrical devices are not 100% efficient because some of the energy is lost as heat or other forms of energy during the process. The energy conversion is not perfect.

The resistance of the stove element can be calculated using Ohm's Law: R = V / I

Therefore, the resistance of the element would be R = (240 V) / (12 A) = 20 ohms.

Turning a light bulb on closes the circuit, allowing the electrical current to flow through it. The current flows from the positive terminal of the battery, through the circuit, and back to the negative terminal.

The electric company will earn $4.00 for the 100 W power generated for 16 hours on Christmas Day.

A pure substance is a substance that has a fixed composition and properties. It cannot be separated into simpler substances by physical means.

A mixture is a combination of two or more substances that are not chemically bonded. It can be separated into its components by physical means.

A chemical change is a change in the chemical composition of a substance. It results in the formation of a new substance with different properties.

A physical change is a change in the physical appearance of a substance but not in its chemical composition. It is reversible.

The periodic table is arranged in horizontal rows called periods and vertical columns called families (or groups).

Non-metals are elements that are generally found on the right side of the periodic table. They are poor conductors of heat and electricity, and they tend to be brittle.

Metalloids are elements that have properties of both metals and non-metals. They are found along the staircase line on the periodic table.

Metals are elements that are generally found on the left side of the periodic table. They are good conductors of heat and electricity, and they are malleable and ductile.