A 45-kg person drinks 390. g of milk, which has a "caloric" value of approximately 3.0 kJ/g. If only 17% of the energy in milk is converted to mechanical work, how high (in meters) can the person climb based on this energy intake? [Hint: The work done in ascending is given by mgh, where m is the mass (in kilograms), g the gravitational acceleration (9.8 m/s2), and h the height (in meters.)]

Answer 1

I presume the 17% means that work from the milk is 3.0 kJ/g x 390 g x 0.17 = ? kJ of work.
Then plug this into work = mgh as shown in the problem and solve for h = height in meters.