A rod AB moves with a uniform velocity v in a uniform magnetic field as shown in figure
(##HCV_VOL2_C38_E01_033_Q01##)

Options

A. `(mg l sin theta)/(2h cos theta)`
B. `(mg l cos^(2)theta)/(2h sin theta)`
C. `(mg l sin theta cos^(2)theta)/(2h)`
D. `(mg l)/(2h sin theta cos^(2)theta)`

Answer

C

Explanation

A uniform ………….

Torque about `X` will be zero
`Txxl_(1)="mg"(l)/(2)sin theta`
`Txx(h)/(cos^(2)theta) = "mg"(l)/(2)sin theta`
`T = (mg lsin theta cos^(2)theta)/(2h)`