Free Current Electricity MCQs with Answers
1,052 Current Electricity MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Steady current relates charge flow to potential difference, resistance and resistivity, including how temperature changes a conductor's resistance. Sources with internal resistance have terminal voltage below their emf when delivering current, and maximum power output occurs under a specific load condition rather than at zero resistance.
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1,052 questions · page 22 of 53
- A. 2.4 A
- B. 240 A
- C. 0.416 A
- D. 41.6 A
- E. 416 A
Explanation: Power = voltages * current100 = 240*ICurrent = I = 10/24= 5/12= 0.4166A
Correct answer: 0.416 A- A. 1.5 A
- B. 10 A
- C. 3.7350 A
- D. 250 A
- E. 100 A
Explanation: The correct answer is 1.5 A. According to Ohm's Law, which states V = I × R, you can determine the current I by rearranging the formula: I…
Correct answer: 1.5 A- A. 125 A
- B. 135 A
- C. 145 A
- D. 155 A
- E. 165 A
Explanation: To determine the current, use the formula I = (E - V) / r, where E is the electromotive force (80V), V is the terminal voltage (75V), and…
Correct answer: 125 A- A. 8 x 10^4 Joules
- B. 12 x 10^5 Joules
- C. 19 x 10^5 Joules
- D. 23 x 10^5 Joules
- E. 37 x 10^5 Joules
Explanation: Energy=Power x time Energy=2000 x 10 x 60 Energy=12 x 10^5 J
Correct answer: 12 x 10^5 Joules425. How much energy is dissipated as heat in 20 s by a 100 Ω resistor that carries a current of 0.5 A?
- A. 50 J
- B. 100 J
- C. 250 J
- D. 500 J
- E. 1,000 J
Explanation: To determine the energy dissipated as heat in a resistor, use the formula: H = I²Rt.
Correct answer: 500 J- A. Series
- B. Parallel
- C. Does not make a difference
- D. Cannot be determined
- E. 160
Explanation: As more and more resistors are added in parallel to a circuit, the equivalent resistance of the circuit decreases, and the total current…
Correct answer: Parallel- A. 1200 Coulombs
- B. 600 Coulombs
- C. 500 Coulombs
- D. 20 Coulombs
Explanation: DATA: Current I = 2 amp Time T = 10 minutes = 600 secCharge Q = ??SOLUTION : I= Q/TQ = ITQ = 600×2 Q = 1200 coloumb ans
Correct answer: 1200 Coulombs- A. Zero
- B. Constant
- C. Increasing
- D. Decreasing
Explanation: The resistance of a conductor decreases with increase in cross-sectional area.
Correct answer: Decreasing- A. Ω x m
- B. Ω - m2
- C. Ω / m
- D. Ω / m2
Explanation: The SI unit of electrical resistivity is the ohm-meter (Ω⋅m). For example, if a 1 m × 1 m × 1 m solid cube of material has sheet contacts…
Correct answer: Ω x m- A. 150 Hz
- B. 100 Hz
- C. 50 Hz
- D. 25 Hz
Explanation: The standard frequency for domestic electricity supply varies around the world, but it is commonly 50 Hertz (Hz).
Correct answer: 50 Hz431. One kilowatt-hour is commonly termed as one commercial unit of electric energy which is equal to:
- A. 3.6 x 10^5 J
- B. 3.6 x 10^6 J
- C. 3.6 x 10^4 J
- D. 3.6 x 10^3 J
Explanation: P = E/tE = P×t = 1000 × 3600P = 3.6 × 106 J
Correct answer: 3.6 x 10^6 J- A. 16R
- B. 4 R
- C. 1 / 16 R
- D. 1 / 4 R
Explanation: Taking volume constant... A- Cross sectional area of wire (pi x r^2) L-Length of wire.
Correct answer: 1 / 16 R- A. Non-linear
- B. Curve
- C. Linear
- D. Curvilinear
Explanation: The resistance increases as the temperature of the metallic conductor increases.
Correct answer: Linear- A. 30
- B. 35
- C. 40
- D. 45
- E. 93
Explanation: V=9 volts R=0.2 ohm I= ? V=IR => I = V/R I = 9 volts / 0.2 ohm I = 45 Ampere So , option D is correct.As this question is theoretical…
Correct answer: 45- A. 9.0 x 10^-7 Ωm
- B. 7.0 x 10^-7 Ωm
- C. 5.0 x 10^-7 Ωm
- D. 3.0 x 10^-7 Ωm
- E. 1.0 x 10^-7 Ωm
Explanation: To solve this problem, start by using Ohm's law, V = IR, to find the resistance (R).
Correct answer: 1.0 x 10^-7 Ωm- A. 9.11 Ω
- B. 2.11 Ω
- C. 3.11 Ω
- D. 1.11 Ω
- E. 0.11 Ω
Explanation: To find the internal resistance of the battery, we can use the formulas:1. The emf, E, is the open-circuit voltage: E = 2.2 V.2.
Correct answer: 1.11 Ω- A. I only
- B. I and II only
- C. II and III only
- D. III and IV only
- E. I, II, III, and IV
Explanation: All of the instruments listed-Wheatstone Bridge, Meter Bridge, Post Office Box, and Ohmmeter-are used for measuring resistance:Wheatstone…
Correct answer: I, II, III, and IV- A. The filament of one of the other bulbs has broken
- B. The filament of the third bulb has broken.
- C. The fuse in the mains transformer has blown.
- D. There is a break in the wire from the supply to the transformer.
Explanation: When a filament of a bulb in a series circuit is broken, it creates an open circuit causing the voltage to be maximum across that bulb.
Correct answer: The filament of the third bulb has broken.- A. 2R/7
- B. R/2
- C. 5R/8
- D. 2R/3
- E. 3R/4
Explanation: Top two resistors placed in series have resistance, R+R=2R1 /R=1 /R+1 /2R=>1/R=3 /2R=> R=2/3*R (for combination two series with one…
Correct answer: 5R/8- A. V
- B. 2V
- C. V/2
- D. V/4
Explanation: At constant voltage, the drift velocity is inversely proportional to the length of the conductor.
Correct answer: V/2