Answer:
The rate at which velocity changes with respect to a change in time is called. acceleration.
Explanation:
Answer:
F=248.5W N
Explanation:
Newton's 2nd Law tells us that F=ma. We will use their averages always. The average acceleration the tennis ball experimented is, by definition:

Since we start counting at 0s and the ball departs from rest, this is just 
So we can write:

Where in the last step we have just multiplied and divided by g, the acceleration of gravity. This allows us to introduce the weight of the ball W since W=gm, so we have:

Substituting our values:

Where the average force exerted has been written it terms of the tennis ball's weight W.
Answer:10m/s
Explanation:
Wave speed ,v=for
Where π= wavelength=2m
Period =1/f f=frequency of wave
F=1/period
=1/0.2=5Hz
So speed of waves,v=5×2=10m/s