# physics

Calculate the energy in kcal used by a
53-kg
woman who does 55 deep knee bends in which her center of mass is lowered and raised
0.400 m.
(She does work in both directions.) You may assume her efficiency is 20%.

1. 👍 0
2. 👎 0
3. 👁 688
1. 27.3

1. 👍 0
2. 👎 1
2. 53x55x9.8x.4

1. 👍 0
2. 👎 1

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