Question
Sun August 12, 2012 By: Siddhanth

A resistive force of 16 N acts on a ball of mass 40 g continuously. If the initial velocity of the ball is 24 ms-1 ,the time taken by it to come to rest is: 0.06s. i checked the method but i didnt seem to understand it????.is there any other method??

Expert Reply
Sun August 12, 2012
Mass of ball: m= 40 g = 0.040kg
resistive force: F = -16 N
thus resistive acceleration, a = F/m (because force, F= ma)
thus a = -400m/s2
initial velocity, u = 24m/s
final velocity, v = 0m/s
Thus according to first equation of motion, v = u+at (t=timetaken)
t= 0.06s
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