Concepts Of Physics MCQ Edition [Volume 2]PhysicsMagnetic Field
A current of 5.0 A flows in a semicircular wire having a radius of 5.0 cm . A magnetic field B with a magnitude of 0.50 T is present perpendicular to the plane of the wire. Determine the magnitude of the magnetic force exerted on this wire.
Options
- A0.39 N
- B0.25 N
- C0.125 N
- D0.79 N
Correct answer
B. 0.25 N
Step-by-step solution
The magnetic force on a current-carrying wire in a uniform magnetic field is given by F = I( L B ) , where L is the displacement vector from the initial point to the final point of the wire. For a semicircular wire of radius R , the magnitude of the displacement vector is the diameter of the semicircle, so L = 2R . Since the magnetic field is perpendicular to the plane of the wire, the angle between L and B is 90^ . The magnitude of the magnetic force is F = I L B (90^ ) = I(2R)B . Given I = 5.0 A , R = 5.0 cm = 0.