PASSPOINTPRO
PHYS 112
GENERAL PHYSICS II
CURRENT, RESISTANCE & DC CIRCUITS
100-QUESTION PRACTICE TEST
Answers, calculations & detailed explanations after every question
100 85 A-D
QUESTIONS CALCULATIONS FORMAT
Current • Ohm's Law • Resistivity • Power • Series & Parallel DC Circuits
, FORMULA REFERENCE
I = Q/t | Q = It
Ohm's law: V = IR
Resistance of a uniform conductor: R = rho L/A
Temperature dependence: R = R0[1 + alpha DeltaT]
Power: P = VI = I^2R = V^2/R
Electrical energy: E = Pt
Series: R_eq = R1 + R2 + ...
Parallel: 1/R_eq = 1/R1 + 1/R2 + ...
Two resistors in parallel: R_eq = R1R2/(R1 + R2)
Real battery during discharge: V_terminal = emf - Ir
Coverage: current and charge flow, Ohm's law, resistivity, temperature effects, power and energy, and basic series/parallel DC circuits.
PassPointPro | PHYS 112 - Current, Resistance & DC Circuits Page 2
, 1. 30 C of charge passes a point in a conductor in 3 s. What is the average current?
A. 20 A
B. 5 A
C. 100 A
D. 10 A
Answer: D - 10 A
Explanation: Current is charge flow per unit time: I = Q/t = 30 C / 3 s = 10 A.
2. A steady current of 1.2 A flows for 10 s. How much charge passes through the
conductor?
A. 6 C
B. 120 C
C. 12 C
D. 24 C
Answer: C - 12 C
Explanation: Use Q = It. Q = (1.2 A)(10 s) = 12 C.
3. How long must a current of 0.4 A flow to transfer 6 C of charge?
A. 30 s
B. 150 s
C. 7.5 s
D. 15 s
Answer: D - 15 s
Explanation: From I = Q/t, t = Q/I = 6/0.4 = 15 s.
4. 18 C of charge passes a point in a conductor in 2 s. What is the average current?
A. 18 A
B. 90 A
C. 4.5 A
D. 9 A
Answer: D - 9 A
Explanation: Current is charge flow per unit time: I = Q/t = 18 C / 2 s = 9 A.
PassPointPro | PHYS 112 - Current, Resistance & DC Circuits Page 3
PHYS 112
GENERAL PHYSICS II
CURRENT, RESISTANCE & DC CIRCUITS
100-QUESTION PRACTICE TEST
Answers, calculations & detailed explanations after every question
100 85 A-D
QUESTIONS CALCULATIONS FORMAT
Current • Ohm's Law • Resistivity • Power • Series & Parallel DC Circuits
, FORMULA REFERENCE
I = Q/t | Q = It
Ohm's law: V = IR
Resistance of a uniform conductor: R = rho L/A
Temperature dependence: R = R0[1 + alpha DeltaT]
Power: P = VI = I^2R = V^2/R
Electrical energy: E = Pt
Series: R_eq = R1 + R2 + ...
Parallel: 1/R_eq = 1/R1 + 1/R2 + ...
Two resistors in parallel: R_eq = R1R2/(R1 + R2)
Real battery during discharge: V_terminal = emf - Ir
Coverage: current and charge flow, Ohm's law, resistivity, temperature effects, power and energy, and basic series/parallel DC circuits.
PassPointPro | PHYS 112 - Current, Resistance & DC Circuits Page 2
, 1. 30 C of charge passes a point in a conductor in 3 s. What is the average current?
A. 20 A
B. 5 A
C. 100 A
D. 10 A
Answer: D - 10 A
Explanation: Current is charge flow per unit time: I = Q/t = 30 C / 3 s = 10 A.
2. A steady current of 1.2 A flows for 10 s. How much charge passes through the
conductor?
A. 6 C
B. 120 C
C. 12 C
D. 24 C
Answer: C - 12 C
Explanation: Use Q = It. Q = (1.2 A)(10 s) = 12 C.
3. How long must a current of 0.4 A flow to transfer 6 C of charge?
A. 30 s
B. 150 s
C. 7.5 s
D. 15 s
Answer: D - 15 s
Explanation: From I = Q/t, t = Q/I = 6/0.4 = 15 s.
4. 18 C of charge passes a point in a conductor in 2 s. What is the average current?
A. 18 A
B. 90 A
C. 4.5 A
D. 9 A
Answer: D - 9 A
Explanation: Current is charge flow per unit time: I = Q/t = 18 C / 2 s = 9 A.
PassPointPro | PHYS 112 - Current, Resistance & DC Circuits Page 3
