A 62.7 kg weight-watcher wishes to climb a
mountain to work off the equivalent of a large
piece of chocolate cake rated at 617 (food)
Calories.
How high must the person climb? The
acceleration due to gravity is 9.8 m/s
2
and 1
food Calorie is 103
calories.
Answer in units of km.

Correction

One food calorie is not 103 calories, rather, 1000 calories

4.2 km

Explanation:

One food calorie is equal to 1000 calories and each calorie has 4.184 J hence for 617 food calories, the energy is equal to 617*1000*4.184

This energy is also given by mgh, the potential energy. M is the mass, g is acceleration due to gravity and h is height in metres.

Substituting 62.7 kg for m, 9.8 for g then

62.7*9.8h=617*1000*4.184