We can solve the problem by using the first law of thermodynamics:

where
is the variation of internal energy of the system
Q is the heat added to the system
W is the work done by the system
In this problem, the variation of internal energy of the system is

While the heat added to the system is

therefore, the work done by the system is

Explanation:
(4566 m / 4 min) × (1 km / 1000 m) × (60 min / h) = 68.49 km/h
Given :
The average acceleration of a tennis ball that has an initial velocity of 6.0 m/s.
and a final velocity of 7.3 m/s.
It is in contact with a tennis racket for 0.094 s
To Find :
The average acceleration of the tennis ball.
Solution :
We know, average acceleration is given by :

Therefore, average velocity is given by 13.83 m/s².
Hence, this is the required solution.
First I’ll show you this standard derivation using conservation of energy:
Pi=Kf,
mgh = 1/2 m v^2,
V = sqrt(2gh)
P is initial potential energy, K is final kinetic, m is mass of object, h is height from stopping point, v is final velocity.
In this case the height difference for the hill is 2-0.5=1.5 m. Thus the ball is moving at sqrt(2(10)(1.5))=
5.477 m/s.
Don't text while driving
don't get your eyes off the road
don't get distracted