Question

Starting from a stationary position, Rahul pedalshis bicycle to attain a velocity of 6 m/s in 30 sec. Then the applied brakes such that the velocity of bicycle comes down to 4 m/s in the next 5 sec. Calculate the acceleration in both the cases.

Answer 1

acceleration = the rate of changeof velocity
                     = (v-u)/t
                      
in the first case,
   v1=6m/sec
u1=0m/sec
t=30 sec

so, a=( 6-0)/30
         =6/30
         =1/5
          0.2m/sec square.

in the second case,
u2= 6m/sec
v2=4m/sec
t= 5sec
so,a= (6-4)/5
       = 2/5
       = 0.4m/sec square.