Question

a body travels with initial velocity of 10km/sec after 30 minutes it came to rest .then calculate the acceleration of the body

Answer 1

Task. A body travels with initial velocity of 10km/sec after 30 minutes it came to rest. Calculate the acceleration of the body.

Solution. Assume that the body moved with constant acceleration $a$. Its initial velocity is

$v_{0}~{}=~{}10~{}km/sec~{}=~{}10*1000~{}m/s=10000~{}m/s$

and it moved during

$t=30~{}min=30*60~{}s=1800~{}s$

and came to the rest, so its final velocity is

$v_{1}=0.$

Therefore

$a=\frac{v_{1}-v_{0}}{t}=\frac{0-10000}{1800}\approx-5.6~{}m/s^{2}.$

Answer. $a=-5.6~{}m/s^{2}$.