Laws Of Motion Question 287
Question: A ball of mass 10 g moving perpendicular to the plane of the wall strikes it and rebounds in the same line with the same velocity. If the impulse experienced by the wall is 0.54 Ns, the velocity of the ball is
Options:
A) $ 27m{{s}^{-1}} $
B) $ 3.7m{{s}^{-1}} $
C) $ 54m{{s}^{-1}} $
D) $ 37m{{s}^{-1}} $
Show Answer
Answer:
Correct Answer: A
Solution:
[a] As the ball, $ m=10\text{ }g=0.01\text{ }kg$
rebounds after striking the wall
$\therefore $ Change in momentum $=mv-(-mv)=2\text{ }mv $
Impulse = Change in momentum $=~2mv$
$\therefore v=\frac{\text{Impulse}}{2m}=\frac{0.54\text{ N s}}{2\times 0.01\text{ kg}}=24\text{ m}{{\text{s}}^{-1}}$
$
