Meta Information  Exercise contained in  Rate this Exercise  



0 
For a top player, a tennis ball may leave the racket on the serve with a speed of $\SI{55}{\meter\per\second}$. If the ball has a mass of $\SI{60.0}{g}$ and is in contact with the racket for about $\SI{4}{ms}$, estimate the average force on the ball.
The ball received a momentum of \begin{align} p &= mv\\ &= \SI{0.060}{kg} \cdot \SI{55}{\meter\per\second}\\ &= \SI{3.3}{\kilo\gram\meter\per\second} \end{align} through the racket. It happend in a time of about $\SI{4}{ms}$, hence the force exerted to the ball is \begin{align} F &= \frac{p}{t} = \frac{mv}{t}\\ &= \frac{\SI{3.3}{\kilo\gram\meter\per\second}}{\SI{0.004}{s}}\\ &= \SI{825}{N} \approx \SI{8e2}{N} \end{align}
19:55, 20. Sept. 2018  signifikanz, text  Urs Zellweger (urs)  Current Version 
07:48, 14. June 2018  si  Urs Zellweger (urs)  Compare with Current 