Quiz for Moving Charges and Magnetism

Q1: What is the direction of magnetic force on a moving positive charge?

A. Perpendicular to both velocity and magnetic field B. Parallel to velocity C. Perpendicular to magnetic field only D. No force is exerted

Q2: Which rule helps to find the direction of magnetic force?

A. Left-hand rule B. Right-hand rule C. Ampere’s rule D. Lenz’s law

Q3: A charge moves in a magnetic field in a circular path. What provides the centripetal force?

A. Gravitational force B. Electric force C. Magnetic force D. Frictional force

Q4: Which formula gives the magnetic force on a charge?

A. F = qvB sinθ B. F = qE C. F = mv²/r D. F = qvE cosθ

Q5: What is the magnetic field at the center of a circular current loop?

A. μ₀I/2r B. μ₀I/4πr² C. μ₀I/2πr D. μ₀Ir²

Q6: What is the path of a charged particle in a uniform magnetic field if velocity is perpendicular to field?

A. Parabolic B. Straight line C. Circular D. Elliptical

Q7: In which case is magnetic force zero?

A. Velocity parallel to B B. Velocity perpendicular to B C. Charge at rest D. Both A and C

Q8: Unit of magnetic field (B) is?

A. Tesla B. Weber C. Newton D. Volt

Q9: Radius of circular path of charged particle in B is proportional to?

A. Charge B. Mass C. Velocity squared D. Magnetic field strength

Q10: Cyclotron frequency is independent of?

A. Magnetic field B. Charge C. Mass D. Velocity

Q11: Lorentz force is the combination of?

A. Electric and magnetic forces B. Gravitational and electric forces C. Magnetic and nuclear forces D. Electric and nuclear forces

Q12: Charge moves at angle θ with B. What is its path?

A. Circular B. Straight line C. Helical D. Random

Q13: Time period of revolution of charge in B field depends on?

A. Speed B. Charge C. Mass and charge D. Radius

Q14: If charge is negative, direction of force is?

A. Opposite to right-hand rule B. Same as right-hand rule C. Zero D. Along velocity

Q15: Charged particle enters B field at angle θ, pitch of helix depends on?

A. Velocity component parallel to B B. Magnetic field strength C. Mass D. Charge

Q16: Which of the following can be used to measure magnetic field strength?

A. Voltmeter B. Ammeter C. Hall probe D. Wheatstone bridge

Q17: What is the force on a stationary charge in magnetic field?

A. Zero B. Maximum C. Depends on direction D. Depends on charge

Q18: If q = 0, what is the magnetic force?

A. Depends on velocity B. Zero C. Maximum D. Depends on field

Q19: SI unit of magnetic flux is?

A. Tesla B. Weber C. Henry D. Ohm

Q20: Magnetic field inside long straight wire carrying current is?

A. Uniform B. Zero C. Increasing linearly with radius D. Decreasing with radius