Question

a moving body is brought to rest within 20 seconds by applying brake find the initial velocity if the retardation due to break is 2m/s

Answer 1

Hey mate here's your answer!!!!!
given
t= 20 sec
a = - 2 m/sec^2
v = 0
as
v = u + at
0 = u + (-2)m/s × 20s^2
- u = - 40m/s
u = 40 m/s