Question

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 content 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

Answer 1

She can climb 0.92 m without losing weight.

Explanation:

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.