Physics CP
Name:______________________________Period:_____________ Date:_____________
Circuits Final Review
Equations:
1. Define a conductor and an insulator. Name a conductor and an insulator.
2. Why are the wires attached to the appliances in your home covered in rubber or
plastic?
3. Why do electrons (not protons) make up the flow through a metal wire?
4. Define current.
5. What is the purpose of a battery in a circuit?
6. What is the difference between potential energy and electric potential?
7. Describe the energy transformations that occur as current flows through a circuit
which has a battery, a resistor, and a light bulb.
8. What is potential difference? What is another name for potential difference?
9. What causes charges to flow around the circuit?
1
2012
Physics CP
2012
Name:______________________________Period:_____________ Date:_____________
10. Define resistance.
11. Do good conductors have high or low resistance?
12. What are the units for each of the following?
Current, Resistance, Charge, Power
13. What are the symbols used for the following in a circuit?
a. Wire
d. Battery or source
b. Open switch
e. Light bulb|
c. Closed switch
f. Resistor
14. What is the main difference between parallel and series circuits? Draw a diagram of
each. Label the source, the potential difference across the battery, the path, and the
resistance.
15. What is constant at every point in a series circuit?
16. How do you determine the total current drawn from a source in a parallel circuit?
17. Draw a schematic diagram for each of the circuits below:
a. A 12 V battery is connected to a 5 Ω resistor.
b. A 12 V battery is connected to two 10 Ω resistors connected in series to
each other.
c. A 9.0 V battery is connected to a 10 Ω resistor connected in parallel to
another 10 Ω resistor.
2
Physics CP
Name:______________________________Period:_____________ Date:_____________
18. What happens to the current in the other light bulbs in a series circuit if one bulb
burns out?
19. Are household circuits normally wired in series or in parallel? Why?
20. What happens to the light intensity of each bulb in a series circuit when more bulbs
are added to the circuit?
21. What happens to the current in the other light bulbs in a parallel circuit if one bulb
burns out?
22. Which has the greater resistance, a thick wire or a thin wire of the same length?
23. Write the equation for Ohm’s law and describe in words what it means.
24. When the equivalent resistance of a circuit is doubled, and no other changes occur,
what effect does this have on the current in the circuit?
25. The headlights of a typical car are powered by a 12 V battery. What is the resistance
of the headlights if they draw a 3.0 A of current when turned on?
26. What is the current in a 20 Ω resistor connected across a voltage of 120 V.
27. What is the voltage across a 100 Ω resistor that has a 0.24 A current flowing through
it?
3
2012
Physics CP
2012
Name:______________________________Period:_____________ Date:_____________
28. Define equivalent resistance.
29. Calculate the equivalent resistance for each of the following circuits.
a. A series circuit containing 10 V battery and 3 lamps, each carrying a
resistance of 3 ohms
b. A parallel circuit containing a 10 V battery and 3 lamps each carrying a
resistance of 3 ohms
30. Which of the two circuits above will draw more current from the battery?
31. A 40 W light bulb and a 75 W light bulb are in parallel across a 120 V outlet. Which
bulb has the greatest current?
32. When a VCR is connected across a 120 V outlet, the VCR draws 9.5 A. What is the
power rating of the VCR?
33. How much current is needed to operate a clock radio that uses 80 W of power from
your household circuit at 120V?
Complete the tables for each of the following circuits.
Find the V, I, R and P values (total, A, B) for the following circuit.
Resistor
voltage
current
Resistance
total (source,
equivalent)
A
Power
B
A
60
120V
4
B
90 Ω
A
Physics CP
2012
Name:______________________________Period:_____________ Date:_____________
Find the V, I, R and P values (total, A, B, C) for the following circuit.
Resistor
voltage
current
Resistance
total (source,
equivalent)
A
Power
B
C
A
A
8Ω
80 V
5
B
16 Ω
C
24 Ω