Question

For a top player, a tennis ball may leave the racket on the serve with a speed of 55 m/s (about 120 mi/h). If the ball has a mass of 0.060 kg and is in contact with the racket for about 4 ms (4 x 10-3 s), estimate the average force on the ball. Would this force be large enough to lift a 60-kg person?

Answer 1

Answer:

Yes is large enough

Explanation:

We need to apply the second Newton's Law to find the solution.

We know that,

$F= ma$

And we know as well that

$a= \frac{v}{t}$

Replacing the aceleration value in the equation force we have,

$F= \frac{mv}{t}$

Substituting our values we have,

$F= \frac{(0.060)(55)}{4*10^{-3}}$

$F=825N$

The weight of the person is then,

$W = mg$

$W = (60)(9.8) = 558N$

We can conclude that force on the ball is large to lift the ball