Question

A skater of mass m standing on ice throws a stone of mass M with a velocity of v m/s in a horizontal direction. Find the distance over which the skater will move back if the coefficient of friction between the skaters and the ice is m.

• A.
• B.
• C.
• D.

Answer 1

The correct option is A

Coservation of momentum yields,

MV = mu $\Rightarrow$ u = $\frac{MV}{m}$ where 'u' is the recoil velocity of the skater.

Since the skater stops after covering a distance 'S'

$\Rightarrow$ $0^2$ - $u^2$ = 2as

$\Rightarrow$ $0^2$ - $u^2$ - 2 (- $\mu$g) s [a = - $\mu$g]

$\Rightarrow$ s = $\frac{u^2}{2\mu g}$