Question

A motor bike is running at 90 km hr-1

is slowed down to 54 km hr-1 by the application of brakes, over a distance

of 40 m. If the brakes are applied with same force, calculate the

(i) total distance travelled by the bike.

(ii) total time in which bike comes to rest.​

Answer 1

Answer:

v²-u²=2as

54²-90²=2a×40/1000

-36×144×1000/80=a

-324000/5=a

a=-64800km/hr²

v=u+at

0=90+(-64800t)

t=-90/-64800hr

s=9/6480×90=81/648km

Answer 2

Answer:

v²-u²=2as

54²-90²=2a×40/1000

-36×144×1000/80=a

-324000/5=a

a=-64800km/hr²

v=u+at

0=90+(-64800t)

t=-90/-64800hr

s=9/6480×90=81/648km