Question

With what minimum velocity should the block be projected from left end $A$ towards end $B$ such that it reaches to the other end $B$ of the conveyor belt moving with constant velocity $v$. The friction coefficient between the block and the belt is $\mu$.

• A. $\sqrt{\mu gL}$
• B. $\sqrt{2\mu gL}$
• C. $\sqrt{3\mu gL}$
• D. $2\sqrt{\mu gL}$

Answer 1

The correct option is B $\sqrt{2\mu gL}$

Energy lost = $\frac{1}{2}m{v}_0^2$
Work against friction = $\mu mgL$
Equating the energies,
$v_0=\sqrt{2\mu gL}$