The body shivers to produce energy and it uses the energy to keep it warm. The body would stop shivering when it has produced enough energy to keep it warm and the atmosphere around it has got warmer
People are asleep at 3 am so energy would be less then.
A line on a graph has a downward slope
Force = (mass) x (acceleration)
= (0.75 kg) x (25 m/s²)
= (0.75 x 25) kg-m/s²
= 18.75 newtons .
Note that even though we're talking about a 'hit', the acceleration only
lasts as long as the bat is in contact with the ball. Once the ball leaves
the bat, it travels at whatever speed it had at the instant when they parted.
Any change in its speed or direction after that is the result of gravity, air
resistance, and the fielder's mitt. I learned a lot about these things a few
weeks ago, since I live in Chicago, about 6 miles from Wrigley Field, in
a house full of Cubs fans.