Question

A gun requiring the support of shoulder shows intensive recoil when fired with:

• A. the butt held tightly with the shoulder.
• B. the butt held loosely against the shoulder.
• C. butt held loosely or tightly against the shoulder.
• D. a bullet of greater mass.

Answer 1

Answer: (B)

the butt held loosely against the shoulder.

Let $m$ be the mass of the bullet and $M$ be the mass of the gun. If $v$ is the velocity of bullet then applying Linear Momentum Conservation
$MV=mv$ i.e., $V=\frac{mv}{M}$
Thus, $V$ is the velocity of recoil of gun when held loosely.
But when the gun is held tightly with the shoulder, the mass of the man supports the gun thus reducing the speed of gun. Hence, the gun experiences intensive recoil when fired with the butt held loosely with the shoulder.