A falling ball weighing 0.8 kg bounces off the floor. The pre-bounce speed is 10.2 m / s and the post-bounce
A falling ball weighing 0.8 kg bounces off the floor. The pre-bounce speed is 10.2 m / s and the post-bounce speed is 6.4 m / s. Find the force that acts on the ball during the moment of rebound 0.12s?
m = 0.8 kg.
V1 = 10.2 m / s.
V2 = 6.4 m / s.
t = 0.12 s.
F -?
According to 2 Newton’s law, the force F, which acts on a body, is equal to the product of the body’s mass m by its acceleration a: F = m * a.
The acceleration of the body a is determined by the formula: a = (V2 – V1) / t and shows how quickly the speed of the body changes over time t.
F = m * (V2 – V1) / t.
Let’s write 2 Newton’s law for projections on the vertical axis of the OU, directed vertically upwards.
F = m * (V2 – (- V1)) / t = m * (V2 + V1) / t.
F = 0.8 kg * (6.4 m / s + 10.2 m / s) / 0.12 s = 110.7 H = 0.11 * 10 ^ 3 H = 0.11 kN.
Answer: at the moment of impact, a force F = 0.11 kN acts on the ball, directed vertically upward.