Question

Find the initial velocity of a car elwhich is stopped in 10 seconds by applying brakes. The retardation due to brakes is 2.5 m/s2

Answer 1

v=0
a=-2.5m/s*s
t=10s

v=u+a*t
0=u+(-2.5)*10
0=u+(-25)
0+25=u
25=u

Answer 2

Question

Find the initial velocity of a car elwhich is stopped in 10 seconds by applying brakes. The retardation due to brakes is 2.5 m/s2

Answer

Time = 10 sec, Retardation = -2.5 m/s^2 and Final velocity = 0 m/s

v = u + at (First Equation Of Motion)

=> 0 = u + (-2.5)(10)

=> 0 = u - 25.0

=> -u = -25.0

=> u = 25 m/s