Question

when brakes are applied to a bus the retardation produced is 25 cm per second and the bus takes 20 seconds to stop calculate the initial velocity of bus and the distance travelled by the bus during this time​

Answer 1

a = -25cm/s

t = 20s

v = 0cm/s

u = ?

v = u + at

0 = u + (-25)(20)

0 = u + (-500)

0+500 = u

•°• u = 500cm/d

Hence the initial velocity of the bus is 500cm/s.

Answer 2

a=-25m/sec

v=0m/sec

t=20sec

u=?

from v=u+at

0=u+(-25) (20)

0=u-500

u=500m/sec