Question

. A car travelling at 36km/h speeds up to 72km/h in 5s. What is its acceleration? If the same car stops in 20 seconds, find retardation.

Answer 1

Answer:

acceleration= 2 m/s2

retardation= -1 m/s2

Explanation:

look,

given u = 36 km/s= 10 m/s

v = 72 km/s = 20 m/s

t= 5s

these all are given to find acceleration

so a= v-u/t

a = 20-10/5

= 10/5

= 2 m/s2

now the initial velocity becomes 20m/s

and the body is going to stop then v= 0m/s

a= v-u/t

= 0-20/20

= -1 m/s2