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 30 of 59
581. 1 Tesla is equal to:
- A. 100 N/Am
- B. 1 N/Am
- C. 0.1 N/Am
- D. 10 N/Am
Explanation: Tesla is the SI unit of magnetic field strength.The magnetic induction will be on Tesla if 1m long wire carrying a current of 1A are…
Correct answer: 1 N/Am- A. Left
- B. Right
- C. Top
- D. Bottom
Explanation: To determine the force on a current-carrying wire in a magnetic field, you can use the right-hand rule.
Correct answer: Left- A. A: Eddy current loss
- B. B: Core loss
- C. C: Copper loss
- D. D: Friction loss
Explanation: The correct answer is D: Friction loss. Transformers are static devices and do not have moving parts; therefore, they do not experience…
Correct answer: D: Friction loss- A. Attract each other
- B. Repel each other
- C. Experience no force between them
- D. None of these options are correct
Explanation: The magnetic force per unit length between two parallel wires is given by; F/ l = (μo/ 2π) (I1I2 / d)If the conductor carries the current…
Correct answer: Repel each other- A. Voltage in primary and secondary are equal
- B. Current in primary and secondary are equal
- C. Input power is same as the output power
- D. Output power is zero
Explanation: A step-up transformer is one that increases voltage, whereas a step-down transformer decreases voltage.Assuming, as we have, that…
Correct answer: Input power is same as the output power- A. 50%
- B. 60%
- C. 90%
- D. 80%
Explanation: efficiency of a transformer can be calculated as:Efficiency= ouput/input x 100 = 100 x 100/ 250 x 0.5 = 80%
Correct answer: 80%- A. VsA-2
- B. V3sA2
- C. V2 s
- D. VsA-1
Explanation: Unit of mutual inductance is VsA^-1 . The unit of mutual inductance is the henry (H).
Correct answer: VsA-1- A. Hysteresis loop
- B. Eddy current
- C. Both
- D. None of these
Explanation: Insulating material between laminations is required for electrical isolation so as to reduce eddy current loss.
Correct answer: Eddy current- A. Eddy current loss will decrease
- B. Eddy current loss will increase
- C. Eddy current loss will remain unchanged
- D. None of these
Explanation: Eddy Current Loss is represented as We = (Ie)2 x RcoreWhere,We = Eddy Current LossIe = Eddy CurrentRe = Resistance of coreSo, as per…
Correct answer: Eddy current loss will remain unchanged- A. Circular
- B. Parabolic
- C. Elliptical
- D. Hyperbolic
Explanation: When the velocity V of charged particle is perpendicular to magnetic field B,the force is always directed towards the center of the…
Correct answer: Circular- A. (1/2)LI^2
- B. LI^2
- C. (3/2)Ll^2
- D. LI
Explanation: An inductor carrying current is analogous to a mass having velocity. So, just like a moving mass has kinetic energy = 1/2 mv2, a coil…
Correct answer: (1/2)LI^2- A. Electrostatic
- B. Magnetostatic
- C. Electromagnetic
- D. None of these
Explanation: As the current changes , the rate of magnetic flux also changes which produces Electromagnetic Field
Correct answer: Electromagnetic- A. 0.01 Wb
- B. 0 Wb
- C. 8.66 x 10^-3 Wb
- D. 0.86 Wb
Explanation: Since the plane is normal (90), the area vector will be ( 90 - 90 ) = 0 with the field.
Correct answer: 0.01 Wb- A. Henry
- B. Farad
- C. Maxwell
- D. Weber
Explanation: SI unit of inductance is henry. Farad is the SI unit of capacitance. Weber is the SI unit of magnetic flux.
Correct answer: Henry- A. Self inductance only
- B. Mutual inductance only
- C. Both Options A and B are correct
- D. E.M.F
Explanation: Inductance, in general, has an SI unit "Henry" (H). Since self and mutual inductance are types of inductance, therefore both will have the…
Correct answer: Both Options A and B are correct- A. Electric energy
- B. Magnetic energy
- C. Electromagnetic energy
- D. Both a and b
Explanation: in an inductor, the energy is stored in the form of magnetic flux.
Correct answer: Magnetic energy- A. Zero
- B. Far apart
- C. Very close
- D. None of these
Explanation: magnetic field is very strong where field lines are very close
Correct answer: Very close- A. Dot product of magnetic field and area vector
- B. Cross product of magnetic field and area vector
- C. Both of these
- D. None of these
Explanation: Magnetic flux = B.AMagnetic flux is dot product of magnetic field and area that is perpendicular to the field.
Correct answer: Dot product of magnetic field and area vector- A. 160N
- B. 120N
- C. 0N
- D. 100N
Explanation: q = 2 C B = 4 T v = 20 m/s F = q ( v × B ) As , q is parallel to B , so , net force acting on charge is 0 N .
Correct answer: 0N- A. Electric field
- B. Magnetic field
- C. Number of turns
- D. None of these
Explanation: l.In step down transformer, Ns < N pStep down transformer reduces voltage and increases current.
Correct answer: Number of turns