Q29 of 124 Page 74

A car of mass 2400 kg moving with a velocity of 20 m s-1 is stopped in 10 seconds on applying brakes. Calculate the retardation and the retarding force.

Mass, m = 2400 kg

Initial velocity, u = 20 m/s


Time, t = 10 s


Final velocity, v = 0 m/s


We know that,


a = v-u/t


=-20/10


=-2 m/s2


Now,


Force, F = ma


=2400 (-2)


= 4800 N


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