Question

a truck running at 90km/h, slows down to 54km/h over a distance of 20m. calculate (a)the retardation produced by its brakes (b) the time for which the brakes are applied.

Answer 1

the Sol is given in the picture . hope you appreciate the solution

Answer 2

Answer:90*5/18=25m0s

54*5/18=15m/s

v^2-u^2 =2as

15^2-25^=2*a*20

225-625=2a*20

2a=400/20

2a=20

a=20/2

a=10m/s^2

v=u+at

15=25-10t

10t=25-15

t=10/10

t=1s

Explanation: