Question

A semicircular wire of radius `r`, carrying a current `I`, is placed in a magnetic field of magnitude `B`. The force acting on it
A. can never be zero
B. can have the maximum magnitude `2Bir`
C. can have the maximum magntidue `Bipir`
D. can have the maximum magnitude `Bir`

Answer 1

Correct Answer - B
To find the Ampere force on a conductor of any shape, replace the conductor by an imaginary straight conductor joining the two ends of the given conductor.