Gravitational Potential Energy of a jump

AI Thread Summary
A high jumper weighing 60.0 kg consumes 3,000 kcal before a jump, with 3.3% of that energy converting to gravitational potential energy. The calculations show that the total energy available is approximately 12,558,000 J, leading to a potential jump height of 705 m using the formula Ug = mgh. However, the textbook states the expected height is 700 m, suggesting a minor discrepancy likely due to rounding. The calculations were verified using Wolfram|Alpha, confirming the accuracy of the approach. The discussion highlights the importance of precision in energy conversion calculations.
liz_p88
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Homework Statement



A high jumper of mass 60.0 kg consumes a meal of 3.00 x 10^3 kcal prior to a jump.
If 3.3% of the energy from the food could be converted to gravitational potential energy in a single jump, how high could the athlete jump?

Homework Equations



Ug = mgh

gravity = 9.8 m/s/s

The Attempt at a Solution



3000 kcal = (4186 J)(3000) = 12,558,000

3.3% of 12,558,000 = 414,414

414,414 J (kg/m^2/s/s) = (60kg)(9.8 m/s/s)(h)

705 m = h

My book says the answer should be 700 m. I got pretty close but I don't know where I might have made a mistake
 
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I get a similar answer to you using Wolfram|Alpha for the calculations. Most likely the discrepancy with the book is due to rounding along some point.
 
That's what I figured. Thank you for double checking for me.
 
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