Question

A 20 kg kid jumps from a moving swing. When she leaves the swing she is y1 “ 1.0 m above the ground, moving with a speed v1 “ 2 m{s at an angle 60 ̋ above horizontal. (a) What is the change in potential energy (∆U ) as she moves from the swing to the ground (y “ 0 m)? (2 pts) (b) Use conservation of mechanical energy (∆K ` ∆U “ 0) to find her speed as she reaches the ground. (3 pts) (c) What is the change in her kinetic energy (∆K) as she moves from the swing to her maximum height? Remember, vy “ 0 at her maximum height, but she has kinetic energy there because she is still moving – the x component of her velocity has not changed. (3 pts) (d) Use conservation of mechanical energy to find the maximum height above the ground that she reaches after jumping from the swing. (2 pts)

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A 20 kg kid jumps from a moving swing. When she leaves the swing
she is y1=1.0 m above the ground, moving with a speed v1=2 m/s at
an angle 60 degrees above horizontal.
(a) What is the change in potential energy (∆U) as she moves
from the swing to the ground (y =0 m)?
(b) Use conservation of mechanical energy (∆K + ∆U = 0) to find
her speed as she reaches the ground.
(c) What is the change...

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