Q27 of 805 Page 169

Velocity versus time graph of a ball of mass 50 g rolling on a concrete floor is shown below. Calculate the acceleration and the frictional force of the floor on the ball?

Given: v = 80 m/s


u = 0 m/s


t = 8 seconds


Now, we know, Acceleration, a = (v-u)/t ...(1)


Where, v = final velocity of the object


u = initial velocity of the object


t is the time-period


a =


a = -10 ms-2


Frictional force = ma


= × -10
= - 0.5 N


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