Question

Than to lift it straight up.

ROPE CLIMBING (2011;3 - AS90940)
A girl of mass 60 kg uses 5 100 J of energy when she climbs a vertical rope.
(a)
Calculate the maximum height it would be possible for the girl to reach.
(b)
In reality, the girl reaches a height of only 8 m.
Explain why the energy used by the girl during the climb does not equal the
work she does to reach the vertical height of 8 m.
In your answer you should:
name the type of energy the girl has when she is 8 m above the ground
calculate the work done to reach a height of 8 m above the ground
calculate the difference between the work done and the energy used by the
girl
•
explain where the "missing" energy has gone, and why this occurs.​

Answer 1

Step-by-step explanation:

(a) PE = mgh

5100 J = (60 kg) (10 m/s²) h

h = 8.5 m

(b) At 8 m, the girl has a gravitational potential energy of:

PE = mgh

PE = (60 kg) (10 m/s²) (8 m)

PE = 4800 J

The difference in energy is 300 J. This energy is converted into heat in the girl's muscles.