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.
Last updated
1,052 questions · page 28 of 53
541. A light bulb draws 300 mA when the voltage across it is 240V. The resistance of the light bulb is:
- A. 400 ohm
- B. 600 ohm
- C. 800 ohm
- D. 1000 ohm
Explanation: The measure of opposition applied by any object to the flow of electric current is known as resistance Resistance = Voltage / Current V=…
Correct answer: 800 ohm- A. As long as possible
- B. As short as possible
- C. Neither too small not too large
- D. Very thick
Explanation: Option A is correct since the slide wire of a potentiometer should be as long as possible for high accuracy so that we have a greater…
Correct answer: As long as possible543. An electric iron is 20V & 500W . The unit consumed by it (in kJ) in using it for 24 hours will be:
- A. 12 units
- B. 24 units
- C. 5 units
- D. 1100 units
Explanation: Power = energy/time500 = E/24E = 500 x 24 = 12,000 J
Correct answer: 12 units- A. Complex network
- B. Wheatstone bridge
- C. Potential divider
- D. All of the above options are correct
Explanation: A potential divider, also known as a voltage divider, is a circuit arrangement composed of resistive elements connected in series.
Correct answer: Potential divider- A. Increase with a rise in temperature
- B. Decrease with a rise in temperature
- C. Will remain the same
- D. Depends upon the altitude of experimentation
Explanation: If we raise the temperature of the metallic conductor, the resistance will increase because in a conductor, as the temperature rises, the…
Correct answer: Increase with a rise in temperature- A. 1
- B. 0.1
- C. 0.01
- D. None of these options are correct
Explanation: E-Vt = I 10-9 = 1V R = V/I = 1/1 = 1 ohm
Correct answer: 1- A. Non-linear
- B. Varying
- C. Linear
- D. None of these options are correct
Explanation: According to Ohm's lawV= IRFor a conductor that obeys Ohm's law, a graph of current I as a function of voltage 'V; is a straight line…
Correct answer: Linear- A. 0.00040 Ohms
- B. 0.060 Ohms
- C. 0.10 Ohms
- D. 0.13 Ohms
Explanation: emf= 1.5 VI = 15 AThe resistance of the ammeter in the circuit is = R = 0.04-ohm I = ε / R + r (r is the internal resistance of the…
Correct answer: 0.060 Ohms- A. Yes
- B. No
- C. Partly
- D. None of these options are correct
Explanation: Those materials for which the slope of the I versus V graph is not constant are called non-ohmic materials.For EXAMPLE The filament of an…
Correct answer: No550. What is the power of a bulb if it is operated at 220V and the current in the circuit is 1.5 Ampere?
- A. 330 watt
- B. 430 watt
- C. 530 watt
- D. 500 watt
Explanation: EXPLANATION:V = 220VI = 1.5 AP = VIP = (220V)(1.5A)P = 330 watt.This is numerical so it can only have one answer so option A is correct.
Correct answer: 330 watt- A. H1=H2
- B. Hl < H2
- C. Hl>H2
- D. None of the above
Explanation: In series resistance, R(series) =R1 †R2 So, H1 =V² /R (series) In parallel 1/R (parallel)=1/R¹ † 1/R²So, H2 =V²/R(parallel)Here, the R…
Correct answer: Hl < H2552. An electrical instrument which is used to measure potential difference between two points is called:
- A. Barometer
- B. Manometer
- C. Galvanometer
- D. Voltmeter
Explanation: Voltmeter, instrument that measures voltages of either direct or alternating electric current on a scale usually graduated in volts…
Correct answer: Voltmeter553. 1 kilo ohm = _ ohm
- A. 103 ohm
- B. 102 ohm
- C. 104 ohm
- D. None of them
Explanation: One kiloohm is equal to 1,000 ohms, which is the resistance between two points of a conductor with one ampere of current at one volt.
Correct answer: 103 ohm- A. Remains the same
- B. Will be doubled
- C. Will become half
- D. Will increase by four times
Explanation: The resistance of a wire is directly proportional to its length and inversely proportional to its cross-sectional area.
Correct answer: Will be doubled- A. D.C. supply only
- B. A.C. supply only
- C. Battery supply only
- D. All above
Explanation: The main work of an electric filament bulb is to glow when an electric current is passed through the electric filament.
Correct answer: All above556. 1 microvolt is
- A. 1 x 10^-3 V
- B. 1 x 10^-4 V
- C. 1 x 10^-5 V
- D. 1 x 10^-6 V
Explanation: One microvolt is equal to 1/1,000,000 of a volt, which is the potential difference that would move one ampere of current against one ohm…
Correct answer: 1 x 10^-6 V- A. Pmax= E2/4r
- B. Pmax = 4rE2
- C. Pmax = VIT
- D. Unlimited
Explanation: It states that the output power of a source of current is maximum, when the internal resistance of the source is equal to the external…
Correct answer: Pmax= E2/4r- A. 0.016 per degree celsius
- B. 32 per degree celsius
- C. 0.018 per degree celsius
- D. 0.00106 per degree Celsius
Explanation: To find the temperature coefficient of resistivity (α) of the material, we can use the formula:α = (R2 - R1) / (R1 * (T2 - T1))Where: α is…
Correct answer: 0.016 per degree celsius559. When 2Ω, 4Ω and 6Ω resistor are connected in parallel their resultant equivalent resistance will be?
- A. 12Ω
- B. 11/12Ω
- C. 12/11Ω
- D. None
Explanation: To find the equivalent resistance of resistors in parallel, we use the formula: 1/Req = 1/R1 + 1/R2 + 1/R3.
Correct answer: 12/11Ω- A. Constant
- B. Varying
- C. All of these options are correct
- D. None of these options are correct
Explanation: Ohm's law states that the voltage across a conductor is directly proportional to the current flowing through it, provided all physical…
Correct answer: Constant