Question

A car travelling at 60km/h uniformly retards for 10 seconds by applying brakes and reaches a velocity of 45 km/h find its retardation

Answer 1

retardation= v-u/t =45-60/10=39
Answer is 39 km/h
can you convert it into m/ s ?

Answer 2

Date:
vi=60km/h
$(60 \times 1000) \div (60 \times 60)$
=16.66
T=10s
Vf=45km/h=12.5
Required:
Retardation of car=a=?
Formula:
Vf=vi+at
on separating the deaccelaration it becomes
a=(vf-Vi)÷T
putting the values
a=(12.2-16.6)÷10
a=-0.4m/s^2
Results:
retardation of car is -0.4m/s^2