Question

In: Physics

A 31.0-kg child on a 3.00-m-long swing is released from rest when the ropes of the...

A 31.0-kg child on a 3.00-m-long swing is released from rest when the ropes of the swing make an angle of 31.0° with the vertical.

(a) Neglecting friction, find the child's speed at the lowest position.

(b) If the actual speed of the child at the lowest position is 2.50 m/s, what is the mechanical energy lost due to friction?

Expert Solution

(a)

First find the height h

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When child reaches lowest position all the potential energy is converted into kinetic energy

ANSWER:

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(b)KE at lowest point will lower if some energy is lost to friction

ANSWER:

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genius_generous answered 6 months ago

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