A rifle of mass fires a bullet of mass with a muzzle speed of relative to the ground

PHYSICS · Single correct · A Level · Physics · Mechanics and materials · Mechanics and materials

Problem

A rifle of mass

4\,\text{kg}

fires a bullet of mass

20\,\text{g}

with a muzzle speed of

300\,\text{m/s}

relative to the ground. Neglecting external forces, what is the recoil speed of the rifle? (a)

0.75\,\text{m/s}

backward (b)

0.15\,\text{m/s}

backward (c)

1.5\,\text{m/s}

backward (d)

3.0\,\text{m/s}

backward