Moving Charges and Magnetism

Q1.A wire of length 1 m carries a current of 5 A in a field of 0.5 T perpendicular to the wire. Force on wire is:

• A0.5 N
• B2.5 N
• C5 N
• D10 N

Q2.What is the force on a current of 5A in the x-direction in a magnetic field of 2T in the z-direction for a length of 3m?

• A30N in y-direction
• B30N in z-direction
• C10N in y-direction
• D30N in x-direction

Q3.A proton enters a cyclotron with kinetic energy 0 and exits with kinetic energy 10 MeV. If it made 100 revolutions, the voltage of the dee is approximately:

• A50 kV
• B100 kV
• C1 MV
• D10 MV

Q4.The magnetic field at the center of a circular arc of radius R, subtending angle φ (in radians) at center, carrying current I is:

• Aμ₀Iφ/(4πR)
• Bμ₀I/(2R)
• Cμ₀Iφ/(2πR)
• Dμ₀I/(4πR)

Q5.The magnetic field at distance r from a long straight wire carrying current I is:

• Aμ₀I/(4πr)
• Bμ₀I/(2πr)
• Cμ₀I/(2r)
• Dμ₀I/r