Question

The food calorie, equal to 4186 J, is a measure of how much energy is released when food is metabolized by the body. A certain brand of fruit-and-cereal bar contains 150 food calories per bar. Part A If a 68.0 kg hiker eats one of these bars, how high a mountain must he climb to "work off" the calories, assuming that all the food energy goes only into increasing gravitational potential energy?

Answer 1

Answer:

The hiker has to climb 941.26 to ''work off'' the calories.

Explanation:

Let's first find out how much energy the hiker gets from 150 food calories.

This is:

Energy = 150 * 4186

Energy = 627.9 kJ

To burn all of this off, we set it equal to the gravitational potential energy, and then solve for the height.

This is:

Gravitational Potential Energy (G.P.E) = 629700

G.P.E = mass * gravity * height

Thus,

mass * gravity * height = 629700

68 * 9.81 * height = 629700

height = 941.26 meters