A 16kg child on a playground swing moves with a speed of 3.4m/s when the 6.0 m long swing is at its lowest point. What angle would the swing make with the vertical, when the swing is at its lowest point?

Question

anonymous · Answer

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jfraser · Answer

I think you mean the $highest$ point on the swing, which is the top of the arc. Use conservation of energy to find the maximum potential energy of the swing, and find the height (change in potential energy)

$SUBTRACT$ that height from the 6.0m swing length, and you'll have the length of the vertical leg of the triangle. You know the hypotenuse is still 6.0m, so find the angle between them