A 0.5 kg ball moving with a speed of 12 m / s strikes a hard wall at an angle of 30° with the wall. It is reflected with the same speed at the same angle. If the ball is in contact with the wall for 0.25 seconds, the average force acting on the wall is

Question

A 0.5 kg ball moving with a speed of 12 m / s strikes a hard wall at an angle of 30° with the wall. It is reflected with the same speed at the same angle. If the ball is in contact with the wall for 0.25 seconds, the average force acting on the wall is (A) 48 N (B) 24 N (C) 12 N (D) 96 N

Tardigrade Admin · Accepted Answer

Here, m=0.5 kg , v=12 m / s , θ=30° t=0.25 s, F= ? As Impulse = change in linear momentum ∴ F × t=2 m v sin 30° (perpendicular to the wall) F=(2 m v sin 30°/t)=(2 × 0.5 × 12/0.25) × (1/2)=24 N.

Q. A $0.5 k g$ ball moving with a speed of $12 m / s$ strikes a hard wall at an angle of $3 0^{\circ}$ with the wall. It is reflected with the same speed at the same angle. If the ball is in contact with the wall for $0.25$ seconds, the average force acting on the wall is

48 N

24 N

12 N

96 N

Here, $m = 0.5 k g, v = 12 m / s, θ = 3 0^{\circ}$
$t = 0.25 s, F =$ ?
As Impulse = change in linear momentum
$∴ F \times t = 2 m v sin 3 0^{\circ}$ (perpendicular to the wall)
$F = \frac{2 m v s i n 3 0 ^{\circ}}{t} = \frac{2 \times 0.5 \times 12}{0.25} \times \frac{1}{2} = 24 N$ .

Q. A 0.5kg ball moving with a speed of 12m/s strikes a hard wall at an angle of 30∘ with the wall. It is reflected with the same speed at the same angle. If the ball is in contact with the wall for 0.25 seconds, the average force acting on the wall is