Answer:

Explanation:
From conservation of energy states that

Answer:

Explanation:

The law of gravitation

Universal gravitational constant [S.I. units]

Mass of Earth [S.I. units]

Mass of a man in a spacecraft [S.I. units]

Earth radius [km]
Distance between man and the earth's surface
![h=261 \mathrm{~km} \quad[\mathrm{~km}]](https://tex.z-dn.net/?f=h%3D261%20%5Cmathrm%7B~km%7D%20%5Cquad%5B%5Cmathrm%7B~km%7D%5D)
ESULT 

Answer:
An object which moves in the positive direction has a positive velocity. If the object is slowing down then its acceleration vector is directed in the opposite direction as its motion (in this case, a negative acceleration).
Explanation:
Answer:
14 seconds
Explanation:
Distance covered by sports car is measured with 21*t where t is time.
Distance covered by police is measured with at^2/2(t-time, a-acceleration) as it doesnt have starting velocity. If the distances are equal(police catches sport car)
then we have 21t=3/2*t^2 Solving this equation we get t=14 & t=0;
excluding the starting point we have 14 seconds