How much momentum will a dumb-bell of mass 10 kg transfer to the floor if it falls from a height of 80 cm? Take its downward acceleration to be 10 ms–2 .

Asked by Vishal kumar | 1 year ago |  368

##### Solution :-

Given, mass of the dumb-bell (m) = 10 kg

Distance covered (s) = 80 cm = 0.8 m

Initial velocity (u) = 0 (it is dropped from a position of rest)

Acceleration (a) = 10ms-2

Terminal velocity (v) =?

Momentum of the dumb-bell when it hits the ground = mv

As per the third motion equation, v2 - u2  = 2as

Therefore, v- 0 = 2(10ms-1)(0.8 m) = 16m2s-2

v = 4 m/s

The momentum transferred by the dumb-bell to the floor = (10 kg) × (4 m/s) = 40 kg.m.s-1

Answered by Shivani Kumari | 1 year ago

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