Question

A ball of mass $200\, g$ rests on a vertical post of height $20\, m$ A bullet of mass $10 \,g$, travelling in horizontal direction, hits the centre of the ball After collision both travels independently The ball hits the ground at a distance $30 \,m$ and the bullet at a distance of $120 \,m$ from the foot of the postThe value of initial velocity of the bullet will be (if $g=10\, m / s ^2$ ) :

• A. $400\, m / s$
• B. $360 \,m / s$
• C. $60 \,m / s$
• D. $120 \,m / s$

Answer 1

Answer: (B)

$360 \,m / s$

Answer 2

The correct answer is (B) : 360 m/s

v1​=g2h​​30​,v2​=g2h​​120​
(0.01)u=(0.2)2h​30g​​+(0.01)2h​120g​​
u=300+60=360ms−1