Free Electromagnetism MCQs with Answers
1,176 Electromagnetism MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Magnetic flux density and magnetic flux describe the strength of a magnetic field and the field passing through a surface. A charged particle moving through a magnetic field experiences a force perpendicular to its velocity and may follow circular or helical motion, depending on the angle between velocity and field.
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Read the Electromagnetism notesFree MDCAT chapter notes with key terms1,176 questions · page 10 of 59
- A. west
- B. Up
- C. Down
- D. Zero
Explanation: Determining Magnetic Force on an Electron Moving Through a Magnetic FieldGiven:- Electron moving north- Magnetic field directed south####…
Correct answer: west- A. 4 volt
- B. 5 volt
- C. 2 volt
- D. 0.4 volt
Explanation: Calculating Potential Difference Across a Moving Coil GalvanometerGiven:- Resistance of the galvanometer (\( R \)) = 100 ohms- Current for…
Correct answer: 0.4 volt- A. Air
- B. Steel
- C. Cu-Ni alloy
- D. Soft iron
Explanation: Determining the Most Suitable Material for an Electromagnet CoreSoft iron is a material widely used for making the core of an…
Correct answer: Soft iron- A. Perpendicular to the field
- B. Parallel to the field
- C. Inclined at some angle to the field
- D. Inclined at an angle of 45⁰
Explanation: Determining the Magnetic Force on a Charged Particle in Different Orientations to the Magnetic FieldWhen a charged particle moves parallel…
Correct answer: Parallel to the field- A. 1T = \(10^3\) G
- B. 1T = \(10^{-4}\) G
- C. T = \(10^{-2}\) G
- D. 1T = \(10^4\) G
Explanation: Relationship Between Tesla and Gauss for Magnetic InductionThe relationship between Tesla (T) and the smaller unit Gauss (G) for magnetic…
Correct answer: 1T = \(10^3\) G- A. Torque = NIA\(_B\) cos(\( \theta \))
- B. Torque = N\(_1\)AB \(\sin(\alpha)\)
- C. Both "a" and "b"
- D. Torque = NIA\(_B\)
Explanation: Torque on a Rectangular Coil Parallel to the Magnetic Field.When the plane of a rectangular coil is parallel to the magnetic field, the…
Correct answer: Torque = NIA\(_B\) cos(\( \theta \))- A. The charge is negative and slowing down
- B. The charge is positive and slowing down
- C. The charge is positive and speeding up
- D. The charge is negative and speeding up
Explanation: When a charged particle moves in a spiral of decreasing radius while being parallel to a uniform magnetic field directed into the page…
Correct answer: The charge is negative and slowing down- A. Will increase.
- B. Will decrease.
- C. Will not change
- D. None of the above
Explanation: In a step-up transformer, the secondary voltage V2 is greater than the primary voltage V1.
Correct answer: Will decrease.- A. 1.6 x 10^-4
- B. 1.6 x 10^-8
- C. 1.6 x 10^-10
- D. 1.6 x 10^-11
Explanation: The force experienced by an electron in an electric field can be calculated using the formula:F= q.EWhere q= 1.6 x 10-19 CE= 108 N/C
Correct answer: 1.6 x 10^-11- A. \(v\) is parallel to and has magnitude \(E/B\)
- B. \(v\) is parallel to
- C. \(v\) is perpendicular to both \(E\) and \(B\) and has magnitude \(B/E\)
- D. \(v\) is perpendicular to both \(E\) and \(B\) and has magnitude \(E/B\)
Explanation: If the velocity were perpendicular to both electric and magnetic fields with a magnitude of \(E/B\), it would imply that the electron's…
Correct answer: \(v\) is perpendicular to both \(E\) and \(B\) and has magnitude \(E/B\)- A. A circle
- B. A spiral
- C. An ellipse
- D. A helix
Explanation: When a charged particle enters a uniform magnetic field with an initial velocity that is not perpendicular to the field, the orbit it…
Correct answer: A spiral- A. \(4\pi \times 10^{-9}\, \text{Wb}\cdot\text{A}^{-1}\)
- B. \(4\pi \times 10^{-7}\, \text{Wb}\cdot\text{A}^{-1}\, \text{m}^{-1}\)
- C. \(4\pi \times 10^{-10}\, \text{Wb}\cdot\text{A}^{-1}\, \text{m}^{-1}\)
- D. \(4\pi \times 10^{-8}\, \text{Wb}\cdot\text{A}^{-1}\cdot\text{m}^{-1}\)
Explanation: The permeability of free space in SI units is represented by:This option represents the correct value for the permeability of free space…
Correct answer: \(4\pi \times 10^{-9}\, \text{Wb}\cdot\text{A}^{-1}\)- A. Voltmeter
- B. Galvanometer
- C. Cathode Ray Oscilloscope (CRO)
- D. Ammeter
Explanation: An instrument capable of measuring potential without drawing any current is:A voltmeter is designed to measure the potential difference…
Correct answer: Voltmeter- A. Zero
- B. \( \frac{cAN}{B} \)
- C. \( \frac{C}{BAN} \)
- D. \( \frac{ABC}{C} \)
Explanation: The sensitivity (\(S\)) of a moving coil galvanometer is determined by the formula:\[ S = \frac{BAN}{C} \]Where:- \(B\) = magnetic field…
Correct answer: Zero- A. Upwards
- B. Away from the magnet
- C. Downward
- D. Toward the magnet
Explanation: Right-Hand Rule Explanation:When electrons move in a wire near the north pole of a magnet, the right-hand rule for current-carrying wires…
Correct answer: Away from the magnet196. The magnitude of force experienced by a stationary charged particle in a uniform magnetic field is
- A. \(qv \times B\
- B. Minimum
- C. Zero
- D. Maximum
Explanation: When a stationary charged particle is placed in a uniform magnetic field, it does not experience any force, assuming it remains…
Correct answer: Zero- A. The core material
- B. The current
- C. The spacing of the windings
- D. The cross-sectional area of the solenoid
Explanation: The magnetic field (\(B\)) inside a long ideal solenoid depends on certain factors while remaining independent of others.Factors affecting…
Correct answer: The current- A. In series with the circuit
- B. In parallel with the circuit
- C. In series with any of the parallel resistances in the circuit
- D. In parallel with any of the series resistances in the circuit
Explanation: An ammeter is used to measure the current flowing through a circuit. Its placement within the circuit affects its ability to accurately…
Correct answer: In series with the circuit- A. \(1.2 \times 10^{-2} \, \text{T}\)
- B. \(2.5 \times 10^{-2} \, \text{T}\)
- C. \(3.0 \times 10^{-2} \, \text{T}\)
- D. \(4.2 \times 10^{-2} \, \text{T}\)
Explanation: The formula for the magnetic field (\(B\)) at the center of a solenoid is given by:\[ B = \mu_0 \cdot n \cdot I \]Where:- \(\mu_0\) =…
Correct answer: \(4.2 \times 10^{-2} \, \text{T}\)- A. Maximum current flows through the galvanometer branch
- B. Minimum current flows through the galvanometer branch
- C. Potential difference across the galvanometer branch is maximum
- D. Potential difference across the galvanometer branch is zero
Explanation: A Wheatstone bridge is considered balanced under specific conditions relating to the current and potential differences within the…
Correct answer: Potential difference across the galvanometer branch is zero