A ball of mass m strikes a rigid wall with speed u and rebounds with the same speed. The impulse imparted to the ball by the wall is

Question

A ball of mass m strikes a rigid wall with speed u and rebounds with the same speed. The impulse imparted to the ball by the wall is (A) 2 mu (B) mu (C) Zero (D) -2 mu

Tardigrade Admin · Accepted Answer

The situation is as shown in the figure.<img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/physics/7d22a50e0f355259f7bb8d8949f42359-.png" /> pinitial=mu, pfinal=-mu Impulse imparted to the ball = Change in momentum =pfinal -pinitial =-mu-mu =-2 mu

Q. A ball of mass $m$ strikes a rigid wall with speed $u$ and rebounds with the same speed. The impulse imparted to the ball by the wall is

$2 m u$

$m u$

Zero

$- 2 m u$

The situation is as shown in the figure.
$p_{ini t ia l} = m u,$ $p_{f ina l} = - m u$
Impulse imparted to the ball = Change in momentum
$= p_{f ina l} - p_{ini t ia l}$ $= - m u - m u$ $= - 2 m u$

Q. A ball of mass m strikes a rigid wall with speed u and rebounds with the same speed. The impulse imparted to the ball by the wall is

2mu

mu