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2 years ago

26. A 40 kg boy jumps from a height of 4m onto a plate-form mounted on springs. As the

Physics

1 answer:

denpristay [2]2 years ago

4 0

Answer:

c. 1600J

Explanation:

The loss in potential energy of the boy is given by:

$U=mg \Delta h$

where

m = 40 kg is the mass of the boy

g = 9.8 m/s^2 is the acceleration of gravity

$\Delta h = 4 m + 0.02 m = 4.02 m$ is the total change in the height of the boy (4 metres + 2 cm due to the compression of the spring)

Substituting, we find

$\Delta U = (40 kg)(9.8 m/s^2)(4.02 m) = 1577 J \sim 1600 J$

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3 years ago

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Andru [333]

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2 years ago

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