Question

A conducting wire MN carrying a current I is bent into the shape as shown and placed in xy plane. A uniform magnetic field `vecB=-Bhatk` is existing in the region. The net magnetic force experenced by the conducting wire MN is
A. 2BIR
B. 3BIR
C. 4BIR
D. 6BIR

Answer 1

Correct Answer - D
Since `vecB` is constant in the region The net magnetic force experienced by the conducting by the conducting wire MN is
`vecF=l(vecL_(eff)xxvecB)`
where `vecL_(eff)=6Rhati`
`vecF=l[6RhatixxB(-hatk)]`
`F=6BlR(hatj)`