Loading test…

AP Physics 2 Unit 3: Electric Circuits

12 questions

Header banner

Unit 3: Electric Circuits

0 of 12 answered

~7 min left

Question 1

Kirchhoff's voltage law (KVL) states that the sum of all voltage drops around any closed loop in a circuit equals zero. This law is a consequence of which fundamental principle?

A.Conservation of chargeB.Conservation of energyC.Newton's third lawD.Ohm's law

Question 2

A resistor has a current of $I = 3 A$ flowing through it and a voltage of $V = 12 V$ across it. What is its resistance?

R = 0.25 Ω

R = 4 Ω

R = 36 Ω

R = 9 Ω

Question 3

Two resistors, $R_{1} = 6 Ω$ and $R_{2} = 3 Ω$ , are connected in parallel across a battery. What is the equivalent resistance of the combination?

R_{eq} = 9 Ω

R_{eq} = 4.5 Ω

R_{eq} = 2 Ω

R_{eq} = 1 Ω

Question 4

An RC circuit has a capacitor $C = 200 μ F$ in series with a resistor $R = 5 k Ω$ and a $12 V$ battery. The capacitor is initially uncharged. Approximately how long after the switch is closed does the voltage across the capacitor reach $7.6 V$ ? (Use $e \approx 2.718$ , so $1 - e^{- 1} \approx 0.632$ .)

t \approx 0.5 s

t \approx 1.0 s

t \approx 2.0 s

t \approx 0.1 s

Question 5

A $6 Ω$ resistor and a $3 Ω$ resistor are connected in parallel. This parallel combination is in series with a $2 Ω$ resistor, and the whole circuit is powered by a $12 V$ battery. What is the current through the $6 Ω$ resistor?

I_{6} = 3 A

I_{6} = 1 A

I_{6} = 2 A

I_{6} = 4 A

In-content ad

Question 6

In a circuit, two batteries are connected in the same loop: Battery 1 has EMF $E_{1} = 12 V$ with internal resistance $r_{1} = 1 Ω$ , and Battery 2 has EMF $E_{2} = 6 V$ with internal resistance $r_{2} = 2 Ω$ . They are connected with opposing polarity (positive terminals facing each other). An external resistance $R = 3 Ω$ completes the loop. What is the current in the loop?

I = 3 A

I = 1 A

I = 2 A

I = 0 A

Question 7

A $12 Ω$ resistor and an $8 Ω$ resistor are connected in series to a $20 V$ battery with negligible internal resistance. What is the voltage across the $8 Ω$ resistor?

V_{8} = 12 V

V_{8} = 8 V

V_{8} = 10 V

V_{8} = 20 V

Question 8

A circuit has a $9 V$ battery with internal resistance $r = 1 Ω$ connected to an external resistance $R = 8 Ω$ . What is the terminal voltage of the battery?

V_{terminal} = 9 V

V_{terminal} = 8 V

V_{terminal} = 1 V

V_{terminal} = 9.1 V

Question 9

A fully charged capacitor ( $C = 100 μ F$ , $V_{0} = 10 V$ ) is connected in series with a resistor $R = 2 k Ω$ with no battery. After the switch is closed, what is the current through the resistor at $t = 0$ (immediately after closing)?

I_{0} = 0

I_{0} = 5 mA

I_{0} = 50 mA

I_{0} = 1 A

Question 10

A $60 W$ lightbulb is designed to operate at $120 V$ . What is its operating resistance?

R = 0.5 Ω

R = 240 Ω

R = 2 Ω

R = 7200 Ω

In-content ad

Question 11

Three resistors are connected between nodes A, B, and C: $R_{A B} = 3 Ω$ (directly between A and B), $R_{B C} = 3 Ω$ (between B and C), and $R_{A C} = 6 Ω$ (between A and C). A $12 V$ battery is connected between A and B. What is the total current delivered by the battery?

I = 4 A

I = 5.33 A

I = 1 A

I = 2.67 A

Question 12

Which of the following best describes what current represents in an electric circuit?

A.The energy per unit charge delivered by the source.B.The rate at which charge flows past a cross section of a conductor.C.The resistance of the conductor to charge flow.D.The power dissipated per unit resistance.

AP Physics 2 Unit 3: Electric Circuits — Free with Answer Explanations | Test Practice Hub