A ball of mass 0.15 kg is dropped from a height 10 m, strikes the ground and rebounds to the same height. The magnitude of impulse imparted to the ball is ( g =10 m / s 2) nearly :

Question

A ball of mass 0.15 kg is dropped from a height 10 m, strikes the ground and rebounds to the same height. The magnitude of impulse imparted to the ball is ( g =10 m / s 2) nearly : (A) 0 kg m/s (B) 4.2 kg m/s (C) 2.1 kg m/s (D) 1.4 kg m/s

Tardigrade Admin · Accepted Answer

Velocity while hitting the ground v =√2 × 10 × 10=10 √2 As it goes to the same height it will return with same speed. So change in velocity v-(-v)=2 v Change in momentum or impulse =2 mv =2 × 0.15 × 10 √2 =3 √2=4.2 kg m / s

Q. A ball of mass $0.15 k g$ is dropped from $a$ height $10 m$ , strikes the ground and rebounds to the same height. The magnitude of impulse imparted to the ball is $(g = 10 m / s^{2})$ nearly :

0 kg m/s

4.2 kg m/s

2.1 kg m/s

1.4 kg m/s

Velocity while hitting the ground
$v = 2 \times 10 \times 10 = 102$
As it goes to the same height it will return with same speed.
So change in velocity $v - (- v) = 2 v$
Change in momentum or impulse
$= 2 m v$
$= 2 \times 0.15 \times 102$
$= 32 = 4.2 k g m / s$

Q. A ball of mass 0.15kg is dropped from a height 10m, strikes the ground and rebounds to the same height. The magnitude of impulse imparted to the ball is (g=10m/s2) nearly :