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.
Last updated
Read the Electromagnetism notesFree MDCAT chapter notes with key terms1,176 questions · page 56 of 59
- A. Wb.m-2
- B. Wb.m2
- C. NAm-1
- D. NmA-1
Explanation: The unit of magnetic flux density is indeed expressed as Weber per square meter (Wb.m-2).
Correct answer: Wb.m-2- A. using a small and thick suspension wire
- B. decreasing the area of the coil
- C. Increasing the magnetic field
- D. reducing the number of turns of the coil
Explanation: The formula for the current sensitivity of a galvanometer is given by: I=cθ/ NAB So, it can enhance the galvanometer's ability to detect…
Correct answer: Increasing the magnetic field- A. 5N
- B. 4N
- C. 2N
- D. 1.5N
Explanation: The force on a wire carrying a current in a magnetic field can be calculated using the formula: F=BILsinθwhere:F is the force,B is the…
Correct answer: 2N- A. Larger
- B. Smaller
- C. Zero
- D. Infinite
Explanation: To make a galvanometer more sensitive, C/(BAN) should be made smaller. This means that for a given current, the galvanometer will show a…
Correct answer: Smaller- A. Iron
- B. Wood
- C. Cobalt
- D. Nickel
Explanation: Nickel, cobalt, and iron are ferromagnetic materials, meaning they can be magnetized or attracted to a magnet.
Correct answer: Wood- A. electric field.
- B. area of the loop.
- C. amount of the current.
- D. direction of the current.
Explanation: A) electric field: The formula for torque on a current-carrying coil in a magnetic field does not involve the electric field.
Correct answer: electric field.- A. be zero.
- B. be maximum.
- C. remain constant.
- D. vary unpredictably.
Explanation: * The force (F) experienced by a current-carrying conductor in a magnetic field is given by the formula: F = I * L * B * sin(theta) Where…
Correct answer: be maximum.- A. area of the coil.
- B. material of the coil.
- C. total number of turns in the coil.
- D. amount of current passing through the coil.
Explanation: The correct answer is Option D: amount of current passing through the coil.
Correct answer: amount of current passing through the coil.- A. 0.018 T
- B. 0.041 T
- C. 0.194 T
- D. 0.541 T
Explanation: To determine the magnetic field B, use the formula for the magnetic force on a current-carrying conductor: F = BIL.
Correct answer: 0.018 T- A. electric field.
- B. magnetic field.
- C. conservative field.
- D. gravitational field.
Explanation: When an electric current passes through a straight wire, it generates a magnetic field around it.
Correct answer: magnetic field.- A. parallel to the magnetic field
- B. perpendicular to the magnetic field
- C. at an angle of 30° to the magnetic field
- D. at an angle of 60° to the magnetic field
Explanation: The correct answer is that the conductor experiences maximum magnetic force when it is perpendicular to the magnetic field.
Correct answer: perpendicular to the magnetic field- A. Force in the magnetic field is doubled.
- B. Length of coil is reduced to half.
- C. Moment arm is reduced to half.
- D. Area of coil is doubled.
Explanation: The torque (τ) on a current-carrying coil in a magnetic field is given by τ = n · I · A · B · sin(θ), where n is the number of turns, I is…
Correct answer: Area of coil is doubled.- A. 0 N.
- B. 10 N.
- C. 100 N.
- D. 1000 N.
Explanation: The force on a current-carrying wire in a magnetic field is calculated using the formula F = BILsinθ.
Correct answer: 1000 N.- A. The area of its coil is made small.
- B. It converts into voltmeter and ammeter.
- C. A small amount of current produces larger deflection.
- D. A small amount of current produces smaller deflection.
Explanation: The correct answer is that a galvanometer becomes more sensitive when a small amount of current produces a larger deflection (Option C).
Correct answer: A small amount of current produces larger deflection.- A. 0.01 N.
- B. 1 N.
- C. 10 N.
- D. 100 N.
Explanation: The force on a current-carrying conductor in a magnetic field is calculated using the formula F = B * I * L, where F is the force, B is…
Correct answer: 1 N.1116. The sensitivity of a galvanometre increases in relation to all of the following EXCEPT for the
- A. Area of the coil.
- B. Amount of current.
- C. Strength of magnetic field.
- D. Number of turns in the coil.
Explanation: The sensitivity of a galvanometer is its ability to detect small changes in current.
Correct answer: Amount of current.- A. Wb.m-2
- B. Wb.m2
- C. Wb
- D. Tesla
Explanation: The unit of magnetic flux is the weber (Wb). In the CGS system, it is measured in maxwells.
Correct answer: Wb- A. Magnetic field is perpendicular to the plane area
- B. Magnetic field lies parallel to the plane area
- C. Area is held at an angle of 45º
- D. Magnetic flux density is perpendicular to area vector of the surface
Explanation: When the magnetic field is perpendicular to the plane of the area (i.e., the angle θ between the magnetic field and the normal to the…
Correct answer: Magnetic field is perpendicular to the plane area- A. Magnetic flux.
- B. Area of the coil.
- C. Shape of the coil.
- D. Resistance of the coil.
Explanation: The correct answer is 'magnetic flux.' According to Faraday's Law of Electromagnetic Induction, the induced electromotive force (EMF) in a…
Correct answer: Magnetic flux.- A. Deflect towards North
- B. Deflect towards South
- C. Move straight
- D. Move in circular path
Explanation: If the particle is moving along the magnetic field, F=0. Hence the particle continues to move along the incident direction, in a straight…
Correct answer: Move straight