Question

A cyclist is cycling at a uniform rate of 8 m/s for 8 s . she then stops padelling the cycle comes to rest in next 10 s. draw velocity time graph.also calculate average velocity of cyclist.

Answer 1

Here,
Initial velocity(u) = 8m/s
Final velocity(v) = 0m/s [Since it comes to rest]
Time taken to stop(t) = 10s

Now, by identity a=u-v/t [Since it is retardation]
                           a=8-0/10
                               =0.8

Again by, S=ut+1/2at*t
S=8*10+1/2*0.8*10*10
S=80+40
   =120

So, Avg. velocity = Total Distance traveled/Total time taken
                               =120/10
                               =12m/s
{Graph in attachment.}