Flashcards: Unit 3 Electricity and Magnetism Practice Test

Front

Which electric component provides energy to the circuit of a flashlight?

Back

battery

Answer explanation

The battery is the component that provides energy to the flashlight circuit, allowing it to function. The motor, resistor, and switch serve different roles but do not supply power.

Front

Effect on current when voltage increases from 25V to 50V with constant resistance.

Back

The current will increase.

Answer explanation

According to Ohm's Law (V = IR), if the voltage (V) increases while resistance (R) remains constant, the current (I) must increase. Therefore, John's increase in voltage from 25 volts to 50 volts will result in an increase in current.

Front

Elaine needs to lower the flow of current in her electric circuit without changing its operation. What part can she add?

Back

a resistor

Answer explanation

Elaine can add a resistor to the circuit. A resistor reduces the flow of current without altering the circuit's operation, making it suitable for lowering the current for the door buzzer.

Front

Device that converts electric energy into light energy for a toy ambulance.

Back

bulb

Answer explanation

The part that converts electric energy into light energy is a bulb. A buzzer produces sound, a motor converts energy into motion, and a switch controls the flow of electricity, but only a bulb emits light.

Front

Which part of a circuit creates an electric force field that makes it possible for the circuit to work?

Back

voltage source

Answer explanation

The voltage source creates an electric force field, providing the necessary energy for the circuit to function. Without it, components like bulbs, buzzers, and motors cannot operate.

Front

Which circuit is a series circuit? Options: [Diagram A], [Diagram B], [Diagram C], [Diagram D]

Back

[Diagram D]

Answer explanation

Diagram D is a series circuit because it shows components connected end-to-end, allowing current to flow through each component sequentially. In contrast, the other diagrams depict parallel connections.

Front

Which device is using a motor?

Back

A body massager uses electric energy to move back and forth.

Front

Which phenomena did Michael Faraday explore to help him invent the motor and the generator?

Back

electricity and magnetism

Front

What’s one advantage of using electromagnets in devices?

Back

Electromagnets can easily be turned on and off.

Front

Which form of energy is a nonrenewable source of energy? Options: hydro (water) energy, geothermal energy, fossil fuel, wind energy

Back

fossil fuel