Question

Мяч массой 100 г, летящий со скоростью 2 м\с, пойман на лету.какова средняя сила удара мяча о руку, если он остановился за 0,02 с?

Answer 1

Calculation of Average Force

To calculate the average force exerted by the ball on the hand, we can use Newton's second law of motion, which states that the force exerted on an object is equal to the rate of change of its momentum. The formula for average force is:

Average Force = Change in Momentum / Time

In this case, the ball is caught on the fly, so its final velocity is zero. The initial velocity of the ball is given as 2 m/s, and its mass is 100 g (or 0.1 kg). The time taken to stop the ball is given as 0.02 s.

First, let's calculate the change in momentum:

Change in Momentum = Final Momentum - Initial Momentum

Since the final velocity is zero, the final momentum is zero. The initial momentum can be calculated as:

Initial Momentum = Mass x Initial Velocity

Substituting the given values:

Initial Momentum = 0.1 kg x 2 m/s = 0.2 kg·m/s

Now, let's calculate the average force:

Average Force = Change in Momentum / Time

Average Force = 0.2 kg·m/s / 0.02 s = 10 N

Therefore, the average force exerted by the ball on the hand is 10 Newtons.