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A 30 kg child on a 2 m long swing is released from rest when the swing supports make an angle of 34 ◦ with the vertical. The acceleration of
Question
A 30 kg child on a 2 m long swing is released from rest when the swing supports make an angle of 34 ◦ with the vertical. The acceleration of gravity is 9.8 m/s 2 . If the speed of the child at the lowest position is 2.31547 m/s, what is the mechanical energy dissipated by the various resistive
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Physics
5 years
2021-09-05T04:47:08+00:00
2021-09-05T04:47:08+00:00 1 Answers
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Answer:
Energy dissipated = 13.453 Joules
Explanation:
In order to solve this problem, we first compute the gravitational potential energy the child has, and then find the kinetic energy at the lowest position.
The gravitational potential energy (relative to lowest position) is found as follows:
G.P.E = mass * gravity * height
Where, Height = 2 – 2 * Cos(34°)
Height = 0.3193 meters
G.P.E = 30 * 9.8 * 0.3193
G.P.E = 93.874 J
Kinetic energy:
K.E = 0.5 * mass * velocity^2
K.E = 0.5 * 30 * 2.31547^2
K.E = 80.421 J
Energy dissipated = G.P.E – K.E
Energy dissipated = 93.874 – 80.421
Energy dissipated = 13.453 J