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 41 of 59
- A. At an angle of 180 degrees with the galvanometer
- B. Parallel with galvanometer
- C. At an angle of 45 degrees with the galvanometer
- D. Perpendicular with the galvanometer
Explanation: Since Galvanometer is a very sensitive instrument therefore it can't measure heavy currents.
Correct answer: Parallel with galvanometer- A. 4 henrys
- B. 8 henrys
- C. 12 henrys
- D. 16 henrys
- E. 20 henrys
Explanation: Initial currect= I1 = 5.0 AFinal current= I2= 0 Achange in current , dI= I1 -I2 =5ATime taken for the change= 0.1sAvg emf= 200Ve=L di/dtL=…
Correct answer: 4 henrys- A. 4 Henrys
- B. 5 Henrys
- C. 6 Henrys
- D. 7 Henrys
- E. 8 henrys
Explanation: Attached below is the solution of question above:
Correct answer: 4 Henrys- A. Electric energy to mechanical energy
- B. Mechanical energy to electric energy
- C. Mechanical energy to potential energy
- D. Not enough information
Explanation: An electric motor transforms electrical energy into mechanical energy. Motors consist of loops of wire in a magnetic field.
Correct answer: Electric energy to mechanical energy- A. Min
- B. Constant
- C. Zero
- D. Max
Explanation: This can be achieved by ensuring that the coils are placed close to each other and that they have a high number of turns.
Correct answer: Max- A. Self inductance only
- B. Mutual inductance
- C. Both Options A and B are correct
- D. EMF
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. Max magnetic flux
- B. Rate of change of magentic flux
- C. Change in magentic flux
- D. Initial flux
Explanation: Faraday's law states that the induced EMF is equal to the rate of change of magnetic flux. Hence, Option B is correct.
Correct answer: Rate of change of magentic flux- A. Genghis Khan
- B. Lenz
- C. Isaac Newton
- D. Michael Faraday
Explanation: Michael Faraday introduced the law of electromagnetic induction. Faraday's law of electromagnetic induction states that a current is…
Correct answer: Michael Faraday- A. Strength of magnetic field
- B. Speed of the conductor
- C. Length of conductor
- D. All answers are correct
Explanation: The factors on which Motional emf depends are, the magnetic field and velocity and length of the rod. Thus option D is the correct answer.
Correct answer: All answers are correct- A. North pole only
- B. Sooth pole only
- C. Both south and north poles
- D. Magnetism will be removed
Explanation: Even if a magnet is broken in half, each half has one north pole and one south pole.
Correct answer: Both south and north poles- A. Constant
- B. Decrease
- C. Increase
- D. Continuously changing
Explanation: Direction of current changes as the coil is rotated
Correct answer: Continuously changing- A. 314 Wb
- B. 107 Wb
- C. 157 Wb
- D. 435 Wb
Explanation: Magnetic flux formula: flux = BA cosθ B = Magnetic Field A = area The angle is the angle between a perpendicular vector to the area and…
Correct answer: 157 Wb- A. Weber
- B. Gauss
- C. Tesla
- D. Maxwell
Explanation: SI unit of Magnetic field induction or Flux density is Tesla (T) or Weber/m2.
Correct answer: Tesla- A. Armature
- B. Magnet
- C. Slip rings
- D. Commutator
Explanation: AC generator does not have commutators. DC generators have commutators to make the current flow in one direction only.
Correct answer: Commutator815. A solenoid is cut into two halves. Magnetic induction due to same current in each half will be:
- A. Half of the original
- B. Double of the original
- C. Same as original
- D. Four times of the original
Explanation: Magnetic field due to a solenoid, B=μo nI. Where n= l/N. So, if the length and number of turns become half for a solenoid, n remains the…
Correct answer: Same as original- A. Clockwise
- B. Anticlockwise
- C. Along PQ
- D. Does not rotate
Explanation: If the given arrangement lies in a horizontal plane; then the rod PQ will rotate clockwise due to the torque.
Correct answer: Clockwise817. When a ferromagnetic material is heated to temperature above its Curie temperature, the material:
- A. Is permanently magnetized
- B. Remains ferromagnetic
- C. Behaves like a diamagnetic material
- D. Behaves like a paramagnetic material
Explanation: When a ferromagnetic material in heated above its curie temperature then it behaves like paramagnetic material.These are metals that are…
Correct answer: Behaves like a paramagnetic material- A. 0.125 wb / m2
- B. 1.25 wb / m2
- C. 12.5 wb / m2
- D. 125 wb / m2
Explanation: B = μ0 / 4π * 2π(qv) / r= 10^-7 × 2 × 3.14 × (1.6 × 10^-19 × 6.6 × 10^15) / 0.53 × 10^-10= 12.5 Wb/m².
Correct answer: 12.5 wb / m2- A. 0.022 Wbm-2
- B. 0.4 Wbm-2
- C. 0.8 Wbm-2
- D. 1 Wbm-2
Explanation: To find the magnetic induction (B) in the center of the coil, we can use the formula: B = (μ₀ * N * I) / L, where:μ₀ (permeability of free…
Correct answer: 0.022 Wbm-2- A. 1 MeV
- B. 4 MeV
- C. 2 MeV
- D. 0.5 MeV
Explanation: By using r = √2mK / qB ; r → same, B → same ⇒ K ∝ q²/mHenceKₐ / Kₚ = (qₐ / qₚ)² × mₚ / mₐ = (2 qₚ / qₚ)² × mₚ / 4 mₚ ⇒ Kₐ = Kₚ = 1…
Correct answer: 1 MeV