Current in Parallel Circuits
The flow of charged particles (electric current) is related to differences in potential energy.
◊ Each student will accurately predict the amount of current leaving a junction, given the amount of current entering a junction. / Name
Date
1
1. What will happen to bulb A if bulb X is removed?
a) Bulb A will become brighter.
b) Bulb A will become dimmer.
c) Bulb A will not change in brightness.
d) Bulb A will not light.
2. What will happen to bulb A if bulb X is removed?
a) Bulb A will become brighter.
b) Bulb A will become dimmer.
c) Bulb A will not change in brightness.
d) Bulb A will not light.
Use this diagram for questions 3-4.
3. What will happen to bulb A if bulb X is removed?
a) Bulb A will become brighter.
b) Bulb A will become dimmer.
c) Bulb A will not change in brightness.
d) Bulb A will not light.
4. What will happen to bulb A if both bulb X and Y are removed?
a) Bulb A will become brighter.
b) Bulb A will become dimmer.
c) Bulb A will not change in brightness.
d) Bulb A will not light.
I.II.
Use this diagram for questions 5-8.
5. Compare the brightness of bulb X to bulb Y.
a) Bulb X is brighter than bulb Y.
b) Bulb X is dimmer than bulb Y.
c) Bulb X is the same brightness as bulb Y.
6. Compare the current in bulb X to the current in bulb Y.
a) Bulb X has more current than bulb Y.
b) Bulb Y has more current than bulb X.
c) Bulb X is the same current as bulb Y.
7. Compare the total resistance of circuit I to circuit II.
a) The resistance of I is greater than the resistance of II.
b) The resistance of II is greater than the resistance of I.
c) The resistance of I is the same as the resistance of II.
8. Compare the total current in circuit I to the total current in circuit II.
a) The current of I is greater than the current of II.
b) The current of II is greater than the current of I.
c) The current of I is the same as the current of II.
Use this diagram for questions 9-10.
9. Select the series that ranks the bulbs from brightest to least bright.
a) A,X,Y
b) A,Y,X
c) X and Y are the same and are both brighter than A
d) A, X and Y are the same and are both dimmer than A
10. Select the series that ranks the bulbs in order of the amount of current passing though each bulb from most current to least current.
a) A,X,Y
b) A,Y,X
c) X and Y are the same and are both brighter than A
d) A, X and Y are the same and are both dimmer than A
I. II.
Use this diagram for questions 11-15.
11. Compare the total resistance of circuit I to the total resistance of circuit II.
a) I has a greater total resistance than II.
b) II has a total greater resistance than I.
c) I and II have the same total resistance.
12. Compare the total current in circuit I to the total current in circuit II.
a) I has a greater total current than II.
b) II has a greater total current than I.
c) I and II have the same total current.
13. Compare the current in resistor X to the current in resistor Y.
a) X has a greater current than Y.
b) Y has a greater current than X.
c) X and Y have the same current.
14. Compare the drop in voltage across resistor X and resistor Y.
a) There is a greater drop in voltage across X than Y.
b) There is a greater drop in voltage across Y than X.
c) There is the same drop in voltage across X and Y.
The drawing above represents a circuit junction.
Current is carried into and away from the junction as shown.
15. How much current leaves the junction through the bottom branch?
a) 1 Ab) 2Ac) 3Ad) 4A
I.II.
16. Match the circuit to the line on the graph.
a) I->A, II->B
b) I->B, II->A
c) both circuits match line A
d) both circuits match line B
17. When resistors are placed in parallel, what happens to the total effective resistance?
18. If you compare a circuit in where the resistors are placed in series to a circuit where the resistors are placed in parallel, which circuit will have a greater current in the circuit?
5. What is the total resistance in the circuit?
a) 4Ωb) 6Ωc) 10Ωd) 0Ω
6. What is the total current in the circuit?
a) 10Ab) 4Ac)6Ad) 1A