Download Final Review CIRCUITS:

Circuits Final Review
1. Why do electrons (not protons) make up the flow through a metal wire?
2. Define current.
3. Describe the energy transformations that occur as current flows through a circuit which has a
battery, a resistor, and a light bulb.
4. What is potential difference? What is another name for potential difference?
5. Define resistance.
6. What are the units for each of the following?
Current:
__________________
Charge:
__________________
Resistance:
__________________
Power:
__________________
7. 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
8. 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.
9. What is constant at every point in a series circuit?
10. 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.
11. What happens to the current in the other light bulbs in a series circuit if one bulb burns out?
12. Are household circuits normally wired in series or in parallel? Why?
13. What happens to the light intensity of each bulb in a series circuit when more bulbs are added
to the circuit?
14. What happens to the current in the other light bulbs in a parallel circuit if one bulb burns out?
15. Which has the greater resistance, a thick wire or a thin wire of the same length?
16. 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?
17. 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?
18. What is the current in a 20 Ω resistor connected across a voltage of 120 V?
19. 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
20. Which of the two circuits above will draw more current from the battery?
21. How much current is needed to operate a clock radio that uses 80 W of power from your
household circuit at 120V?
22. 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
B
90 Ω
A
120V
Resistor
total (source,
equivalent)
A
voltage
current
Resistance
Power
B
C
A
80 V
A
8Ω
B
16 Ω
C
24 Ω