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 26 of 53
- A. Magnetic field
- B. Both
- C. None of these
- D. Electric field
Explanation: A steady current in a wire constitutes a concentric magnetic field perpendicular to the direction of the current in the said wire.
Correct answer: Magnetic field- A. Remain constant
- B. Decrease
- C. None of these
- D. Increase
Explanation: The terminal potential difference (V) is given by V = E - Ir.where E is the electromotive force, I is the current, and r is the internal…
Correct answer: Decrease- A. None
- B. Length
- C. Nature of material
- D. Temperature
Explanation: Resistance is directly proportional to the length of the wire the current is passing through.
Correct answer: Length- A. P = VR
- B. P = VIR/t
- C. P = V/Q
- D. P = IV
Explanation: Power is defined as the amount of energy used per unit of time or the rate of doing work.
Correct answer: P = IV505. Volts / Ampere = _
- A. Ohm
- B. Ohmmeter
- C. Pascal
- D. None of them
Explanation: Volt Per Ampere (V/A) is a unit in the category of Electric resistance. It is also known as volts/ampere, volts/amp.
Correct answer: Ohm- A. 100W
- B. 200W
- C. 300W
- D. 60W
Explanation: From the given information in the question, Power = VI. That is, voltage times the current.
Correct answer: 300W- A. Increases with increase in its internal resistance
- B. Decrease with an increase in internal resistance
- C. Is independent of its internal resistance
- D. None of these
Explanation: We know that terminal potential difference V = E -IrBy increasing the internal resistance, Ir factor increases which causes decrease in…
Correct answer: Decrease with an increase in internal resistance- A. 3 ampere
- B. 3 volts
- C. 2 amperes
- D. 2 volts
Explanation: We know that I = q/tHereI = currentq = charget = timein a conductor, if 6 coulomb charge flows per 2 secondsHenceq = 6 Ct = 2…
Correct answer: 3 ampere- A. 333.3 ampere
- B. 333.33 volts
- C. 666.67 ampere
- D. None of them
Explanation: To calculate the current, we can use Ohm's Law, which states that current (I) isequal to the charge (Q) passing through a conductor…
Correct answer: 333.3 ampere- A. 0.9 Amp
- B. 0.6 Amp
- C. 2 Amp
- D. 3 Amp
Explanation: Electrical Power is found as the product of Voltage and Current, so here Current can be found by dividing the Power by the Voltage…
Correct answer: 0.9 Amp- A. Minimum
- B. Constant
- C. Maximum
- D. Varying
Explanation: The potential difference is the amount of work done in moving a unit positive charge without acceleration from one point to another along…
Correct answer: Constant- A. 150V
- B. 250V
- C. 50V
- D. 15V
Explanation: The potential difference across a conductor is given by Ohm's Law V = IR where V is the potential difference, I is the current, and R is…
Correct answer: 250V- A. 1 x 10^-7
- B. 2.63 X 10^-8
- C. 19 X 10^-8
- D. 7.85 x 10^-8
Explanation: For resistivity , first we have to find out resistanceV = I RSo R = V / IR = 1.5 / 0.75R = 2 ohmsR = l / A = resistivity length / area = R…
Correct answer: 1 x 10^-7- A. Same
- B. Different
- C. Both of them
- D. None of them
Explanation: In a parallel circuit, the voltage across each branch of the circuit is the same as the voltage across the voltage source.
Correct answer: Same- A. L, 2A
- B. L/2, 2A
- C. 2L, 2A
- D. 2L, A/2
Explanation: b) L/2, 2A This option suggests that to minimize resistance, the length (L) of the copper piece should be halved (L/2), and the…
Correct answer: L/2, 2A- A. 2 kWh
- B. 20 kWh
- C. 6 kWh
- D. 12 kWh
Explanation: To calculate the electrical power consumed by the immersion heater, you can use the formula: Power (P) = Voltage (V) × Current (I) Given…
Correct answer: 2 kWh517. If the length of a potentiometer wire is doubled, the accuracy in determining the null point _.
- A. Is increased
- B. Is decreased
- C. Remains constant
- D. May increase or decrease
Explanation: Option A is correct: Doubling the length of the potentiometer wire enhances the accuracy in determining the null point.
Correct answer: Is increased- A. 1 KWh
- B. 1.5 KWh
- C. 2 KWh
- D. 3 KWh
Explanation: 1kWh is the power output multiplied by the number of hours the appliance is used.
Correct answer: 1.5 KWh519. A potentiometer is used to measure the emf of a cell. At null point, no current flows through _.
- A. The main circuit
- B. The cell circuit
- C. Both the main and cell circuits
- D. The potentiometer wire
Explanation: At the null point of a potentiometer, the potential difference across the potentiometer wire is equal to the emf of the cell being…
Correct answer: The cell circuit- A. 250 seconds
- B. 350 seconds
- C. 400 seconds
- D. 500 seconds
Explanation: Current can be found by dividing the charge in Coulombs by the time taken in seconds, (5000/20) hence time taken is 250 seconds.
Correct answer: 250 seconds