Cord Tie

multiple choice, what's the answer?

A woman performs a 'bungee jump', falling from a bridge with a length of elastic cord tied around her ankles. The gravitational potential energy of lost by the jumper at the lowest point has been transferred as:
A elastic strain energy in the cord.
B elastic strain energy and internal energy in the cord
C kinetic energy of the jumper OR
D kinetic energy of the jumper plus internal energy in the cord.

With reasons please. Thanks a lot.

Like all multiple choice you have to read carefully. The key bit is "at the lowest point".

At the lowest point the jumper has no velocity as their velocity is right at the point between going down and going up. So they have no kinetic energy. This rules out C and D.

Most of the energy will be transfered to the strain energy is the cord so it is A or B. However the transfer is not perfect and there will also be heat generated. Not sure what is meant by "internal energy in the cord" I would argue this includes heat in the cord. On that basis I would go with answer "B".

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KOKUYO linen cord tie color 520 m cheese winding Hochi 31
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Heavy Duty Bungee Cords with Hooks Proudly Made in USA By SUPER SMITHEE Tie Down
Heavy Duty Bungee Cords with Hooks Proudly Made in USA By SUPER SMITHEE Tie Down
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