Practice identifying circuit parts, comparing series and parallel circuits, and using basic relationships among voltage, current, and resistance.
Read each problem carefully. Show your work when calculations are needed. Use complete sentences for explanations.
Exploring current, voltage, resistance, and simple circuits
Physics - Grade 6-8
- 1
A simple circuit has a battery, wires, and one light bulb. Explain why the bulb lights only when the circuit is closed.
- 2
Define electric current in your own words.
- 3
A circuit has a 9 volt battery and a 3 ohm resistor. Use Ohm's law, V = I × R, to find the current.
- 4
Look at a circuit with two light bulbs connected one after the other in the same loop. Is this a series circuit or a parallel circuit? Explain.
- 5
In a series circuit with two bulbs, one bulb burns out and creates an open gap. What happens to the other bulb? Explain why.
- 6
In a parallel circuit, two bulbs are connected on separate branches. One bulb burns out. What happens to the other bulb? Explain why.
- 7
A student builds a circuit with a battery, a switch, wires, and a buzzer. What is the purpose of the switch?
- 8
Classify each material as a conductor or an insulator: copper wire, rubber, aluminum foil, plastic spoon.
- 9
A circuit has a current of 2 amperes flowing through a 5 ohm resistor. Use Ohm's law to find the voltage across the resistor.
- 10
Two circuits each use the same battery and identical bulbs. Circuit A has one bulb. Circuit B has three identical bulbs in series. Which circuit's bulbs will usually be dimmer? Explain.
- 11
A resistor has a voltage of 12 volts across it and a current of 4 amperes through it. What is its resistance?
- 12
Explain the difference between voltage and current.
- 13
A diagram shows a battery connected to a bulb, but one wire is not attached to the battery terminal. Will the bulb light? Explain.
- 14
A student says, 'Batteries create electrons that flow through wires.' Correct this statement using what you know about circuits.
- 15
A circuit has a battery, a switch, and two bulbs connected in parallel. Draw or describe the path current can take when the switch is closed.