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 35 of 59
- A. Compton's effect
- B. Photoelectric effect
- C. Coulomb's effect
- D. Faraday's law
- E. Ohm's law
Explanation: The photoelectric effect is a phenomenon in which electrons are ejected from the surface of a metal when light is incident on it.
Correct answer: Photoelectric effect- A. 2.6 x 10 19C;36. x 10 28 kg
- B. 1.6.x 10 19C;1.673 x 10^-27kg
- C. 3.6 x 10 19C ;2.111 x 10^27kg
- D. 4.6 x 10 19 C;9.111 x 10^27kg
- E. 5.6 x 10 19C ;8.111 x 10^27kg
Explanation: Therefore, the given answer of 1.6 x 10 19 C for the charge of a proton and 1.673 x 1027 kg for the mass of a proton is correct.
Correct answer: 1.6.x 10 19C;1.673 x 10^-27kg- A. 0°
- B. 90°
- C. 180°
- D. 270°
Explanation: 90 degrees: This is the correct option. As explained earlier, the magnetic field lines form concentric circles around the conductor, and…
Correct answer: 90°- A. A
- B. B
- C. C
- D. D
Explanation: The field produced by the bar magnet is non uniform. As we move the magnet towards the coil the flux would increase to a certain value.
Correct answer: A- A. 0.23 Tesla
- B. 1.11 Tesla
- C. 2.15 Tesla
- D. 4.37 Tesla
Explanation: Given the graph showing a straight line from (0,0) to (3,0.7) with a constant gradient, we need to determine the magnitude of the magnetic…
Correct answer: 0.23 Tesla- A. A
- B. B
- C. C
- D. D
Explanation: Coil 1:Current B → A = anticlockwise → north pole toward magnet ▪ Coil 2:Current D → C = clockwise → south pole toward magnet Option B is…
Correct answer: B- A. Pressure and magnetism
- B. Pressure and electric flux
- C. Temperature and magnetism
- D. Temperature and electric flux
Explanation: The Curie point refers to the temperature at which certain materials undergo a phase transition, causing a significant change in their…
Correct answer: Temperature and magnetism- A. 0.23 x 10^-1 T
- B. 1.67 x 10^-4 T
- C. 2.99 x 10^-6 T
- D. 3.63 x 10^-8 T
- E. 999 x 10^-7 T
Explanation: Magnetic flux density is the number of lines of force that pass through a point on a specific surface.
Correct answer: 1.67 x 10^-4 T- A. Electric, Mechanical
- B. Mechanical , Electric
- C. Mechanical , Potential
- D. Not enough information is available
Explanation: An electric motor is an electrical machine that converts "electrical energy" into "mechanical energy", opposite to an electric generator…
Correct answer: Electric, Mechanical- A. Changing magnetic fields in space
- B. Changing magnetic field in time
- C. Changing flux with space
- D. Constant magnetic field
Explanation: A motional EMF is the EMF induced by a conductor moving through a constant magnetic field.
Correct answer: Constant magnetic field- A. 0 degree
- B. 90 degree
- C. 45 degree
- D. 60 degree
Explanation: According to the formula,ΦB = BAcosθWe know that cosθ gives its maximum value (1) when θ = 0°.ΦB = BAcos0°ΦB = BA(+1)ΦB = BAHence, option…
Correct answer: 0 degree- A. A
- B. B
- C. C
- D. D
Explanation: As we know F = qvB sin θ. Where θ is the angle between the velocity and the magnetic field, a greater angle leads to maximum force.
Correct answer: C- A. Momentum
- B. Speed
- C. Velocity
- D. None of these
Explanation: Following is the solution to this question:
Correct answer: Speed- A. 5 x 10^9 C / kg
- B. 2.5 x 10^11 C / kg
- C. 5 x 10^11 C / kg
- D. 5 x 10^12 C / kg
Explanation: Following is the solution to this question:
Correct answer: 2.5 x 10^11 C / kg- A. one direct voltage to another direct voltage of different magnitude.
- B. one alternating voltage to another alternating voltage of different magnitude.
- C. a high value alternating voltage to low value direct voltage.
- D. A high value alternating current to low value direct voltage
Explanation: A transformer converts a high voltage low current alternating current to a low voltage high current one and vice versa.
Correct answer: one alternating voltage to another alternating voltage of different magnitude.- A. Eddy's current
- B. Surge current
- C. Leakage current
- D. Steady current
Explanation: The DC current which does not change its intensity is known as steady current. Hence option D is correct.
Correct answer: Steady current- A. Self induction
- B. Mutual induction
- C. Motional EMF
- D. Magnetic torque
Explanation: Transformer works on the principal of mutual induction, according to which; "The phenomenon in which a changing current in one coil…
Correct answer: Mutual induction- A. Output voltage is half of input voltage
- B. Output and input voltages are equal
- C. Output voltage is double the input voltage
- D. Output voltage is zero
Explanation: Using formula; Np/Ns = Vp/ Vs 500/250 = Vp/Vs 2 = Vp/Vs So Vp = 2Vs or Vs = Vp/2 Hence, secondary voltage or output voltage is half of…
Correct answer: Output voltage is half of input voltage- A. Magnetic field
- B. Magnetic force
- C. Magnetic dipole
- D. Magnetic flux density
Explanation: Change in magnetic flux per unit area is Φ/A which is equal to B i.e. magnetic flux density. Φ = B . A Hence, option D is correct.
Correct answer: Magnetic flux density- A. Magnetic flux
- B. Magnetic induction
- C. Magnetic field
- D. Magnetic pole
Explanation: Magnetic induction per unit Area is B/A which is equal to Φ i.e., magnetic flux Φ = B . A Hence, option A is correct.
Correct answer: Magnetic flux