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A 30kg child is swinging on a swing whose seat is a distance of 5.0m from the pivot point. Estimate the optimal time between “pumps” that the child should execute to increase her swinging amplitude. How does this time change for a 15.0 kg child?
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A 30kg child is swinging on a swing whose seat is a distance of 5.0m from the pivot point. Estimate the optimal time between “pumps” that the child should execute to increase her swinging amplitude. How does this time change for a 15.0 kg child? • (9 got this right, 3 made a slight error, 32 didn’t answer and 10 didn’t know what to do). • I know that the problem probably involves T = 2 (pi) (L/g)^(1/2), but I don't know how to proceed (for someone who did not know what to, this is VERY GOOD!) • Since this is just an estimation, I used the equation T = 2 x pi (L/g)^1/2 where the mass is all concentrated at the end of the pendulum. So with L=5.0m, the optimal time is 4.5 seconds. Since the mass is not in this equation, the weight of the child doesn't matter. (This is the period; depending on how you pump this is the answer, or half this time, or some multiple of this time).
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