a girl on a swing, which is 4 m long, is 2.0 m high at her highest point (all the way back) and 0.5 m above the ground at the closest point (at the bottom).(adsbygoogle = window.adsbygoogle || []).push({});

question is how fast is she going and when?

im pretty sure her fastest point is at the bottom.

to solve it i think you set potential energy equal to kinetic (mgh = 1/2mv^2) and solve for v. but what h do you use? is it 2.0 m or 1.5 m (the difference in heights from top to lowest point)?

also, whats the point in mentioning the 4 m long string?

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# Homework Help: Conservation of energy question

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