A boy weighing 55 kg jumped at a speed of 2.8 m / s to the shore from a stationary boat. With what speed did the boat

A boy weighing 55 kg jumped at a speed of 2.8 m / s to the shore from a stationary boat. With what speed did the boat begin to move after the boy’s jump, if the weight of the boat was 28 kg?

To find out the speed acquired by the indicated boat, we use the equality (s-n of conservation of momentum): mm * Vm = ml * Vlx, from where we express: Vlx = mm * Vm / ml.

The given tasks: mm is the mass of the jumping boy (mm = 55 kg); Vm – the boy’s jump speed (Vm = 2.8 m / s); ml – the mass of the indicated boat (ml = 28 kg).

Let’s perform the calculation: Vlx = mm * Vm / ml = 55 * 2.8 / 28 = 5.5 m / s.

Answer: After the boy’s jump, the indicated boat should have started moving at a speed of 5.5 m / s.



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