Andra is playing tennis using a ball with mass of 100 g. The ball is coming near to him with velocity of 10 m/s. Andra hits back the ball with a force of 120 N. If the racket touches the ball for 0.02 s. The velocity of the ball after collision is... m/s. A. 20 B. 16 C. 14 D. 8 E. 6
We can use the principle of conservation of momentum to solve this problem. Since there are no external forces acting on the ball-racket system, the total momentum before and after the collision must be equal.
Let's first find the momentum of the ball before the collision:
p_before = m*v_before
where
m = 100 g = 0.1 kg (mass of the ball)
v_before = 10 m/s (velocity of the ball)
p_before = 0.1 kg * 10 m/s = 1 kg m/s
During the collision, the racket applies a force of 120 N for 0.02 s, which changes the momentum of the ball. The change in momentum is given by:
Δp = F*t
where
F = 120 N (force applied by the racket)
t = 0.02 s (time of contact)
Δp = 120 N * 0.02 s = 2.4 kg m/s
The final momentum of the ball can be calculated as:
p_after = p_before + Δp
p_after = 1 kg m/s + 2.4 kg m/s = 3.4 kg m/s
Finally, we can find the velocity of the ball after the collision using the equation:
p_after = m*v_after
v_after = p_after / m
v_after = 3.4 kg m/s / 0.1 kg = 34 m/s
Therefore, the velocity of the ball after the collision is 34 m/s, which is not one of the answer choices. We may have made an error in our calculations or assumptions, or the answer choices may not be accurate.
Jawaban:
We can use the principle of conservation of momentum to solve this problem. Since there are no external forces acting on the ball-racket system, the total momentum before and after the collision must be equal.
Let's first find the momentum of the ball before the collision:
p_before = m*v_before
where
m = 100 g = 0.1 kg (mass of the ball)
v_before = 10 m/s (velocity of the ball)
p_before = 0.1 kg * 10 m/s = 1 kg m/s
During the collision, the racket applies a force of 120 N for 0.02 s, which changes the momentum of the ball. The change in momentum is given by:
Δp = F*t
where
F = 120 N (force applied by the racket)
t = 0.02 s (time of contact)
Δp = 120 N * 0.02 s = 2.4 kg m/s
The final momentum of the ball can be calculated as:
p_after = p_before + Δp
p_after = 1 kg m/s + 2.4 kg m/s = 3.4 kg m/s
Finally, we can find the velocity of the ball after the collision using the equation:
p_after = m*v_after
v_after = p_after / m
v_after = 3.4 kg m/s / 0.1 kg = 34 m/s
Therefore, the velocity of the ball after the collision is 34 m/s, which is not one of the answer choices. We may have made an error in our calculations or assumptions, or the answer choices may not be accurate.