Question

20. When brakes are applied, the velocity of a car changes from 40 m s-1 to 10 m s-1 in 10 s. The acceleration produced in it is ms2 (b) 3 (d) 5 (a) -3 (c) 5 .​

Answer 1

Answer:

Explanation:

initial vel. u=40m/s

final vel. v=10m/s

time t=10s

as the speed of car is reducing,it is deceleration,so -a

applying equation v=u+at

40=10+(-a)*10 ⇒ 40=10-10a ⇒ 10a=-30 ⇒ a= -3m/s²

so acceleration= -3m/s²