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3 years ago

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A student has a mass (including clothes and shoes) of 65.0 kg. She drinks a 12 oz. can of soda, with a nutritional energy conten

t of 140 Cal. Assuming that the efficiency of her muscles is 20%, how high can she climb without losing weight?
Conversion: 1 Cal = 1,000 cal = 4,180 J

1 answer:

Stella [2.4K]3 years ago

7 0

She can climb 0.92 m without losing weight.

<u>Explanation</u>:

Gravitational potential energy is the energy consisting of the product of mass, gravity and height.

1 cal = 4184 J

140 cal = 585760 J

Energy = 585760 J, m = 65.0 kg = 65000 g, Efficiency = 20 %

GPE = mgh

where m represents the mass

g represents the gravity,

h represents the height.

585760 = 65000 $\times$ 9.8 $\times$ h

h = 0.92 m.

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