Free Magnetic Flux Density MCQs with Answers
96 Magnetic Flux Density 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 measures the magnetic force acting on a current carrying conductor or moving charge in a magnetic field. Work includes the relations B equals F divided by IL and F equals qvB, the tesla as its SI unit, field direction and the distinction between flux density and magnetic flux.
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96 questions · page 4 of 5
- 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.- 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. Inversely with r
- B. Inversely with r2
- C. Directly with r2
- D. Directly with r
Explanation: To find the magnetic field at a radius r inside the wire, draw a circular loop of radius r.
Correct answer: Directly with r- A. Magnetic flux
- B. Magnetic induction
- C. Work done
- D. Magnetic Force
Explanation: The dimensions of magnetic field strength (B) are the same as those of magnetic induction, which is Newtons per Ampere-meter (N/A·m).
Correct answer: Magnetic induction- A. µI2
- B. µ/I
- C. µI
- D. Iµ2
Explanation: Ampere's law states that the sum of the dot product of the tangential components of magnetic induction (B) and, the respective length of…
Correct answer: µI- A. 4π x 10-7 WbA-1m-1
- B. 4π x 102 WbA-2m-2
- C. 4π x 10-7 WbA-2m-1
- D. 4π x 102 WbA-1m-2
Explanation: Explanation: The value of permeability of free space μo is 4π × 10-7 WbA-1m-1.
Correct answer: 4π x 10-7 WbA-1m-1- A. 1 Wb m-2 = N m-1 A-1
- B. 1 Tesla = 104 Gauss
- C. 1 Wb m-2 = 1 Tesla
- D. All of these
Explanation: Option D is the correct choice because all the given relations are accurate.
Correct answer: All of these- A. τ = NIAB cos α
- B. τ = BIL sin α
- C. τ = NIAB sin α
- D. τ = BIL cos α
Explanation: The correct formula for the torque acting on a current-carrying coil is τ = NIAB cos α.
Correct answer: τ = NIAB cos α- A. Increasing magnetic field
- B. Increasing the number of turns of the coil
- C. Increasing the c/BAN ratio
- D. Decreasing the length of couple 'c'
Explanation: Sensitivity of a galvanometer is defined as the deflection per unit current.
Correct answer: Increasing the c/BAN ratio- A. F = NIA cos α
- B. F = μnI
- C. F = ILB sin α
- D. F = ILA cos α
Explanation: The correct formula for the force exerted on a current-carrying conductor in a uniform magnetic field is F = ILB sin α.
Correct answer: F = ILB sin α- A. F/2
- B. 2F
- C. F/√2
- D. √2 F
Explanation: As we know, the force experienced by the current-carrying conductor is given by F'=IBLsinθ If θ= 45o F'=Fsin45° F'=F(0.707) F'=F/√2
Correct answer: F/√2- A. Half
- B. Double
- C. Eight-times
- D. Four-times
Explanation: As we know, the force experienced by the current-carrying conductor is given by F=IBL (sinθ=1) F'=IBLsinθ If = 90o If all other…
Correct answer: Eight-times- A. 0°
- B. 30°
- C. 90°
- D. 60°
Explanation: The maximum force on a current-carrying conductor occurs when the current direction and the magnetic field's direction are perpendicular…
Correct answer: 90°- A. Parallel to the conductor
- B. In clockwise direction
- C. Anticlockwise direction
- D. None of these
Explanation: The direction of magnetic field in the conductor can be found out by right hand thumb rule.
Correct answer: Anticlockwise direction