Question

A student eats a dinner rated at 1533 (food) Calories. He wishes to do an equivalent amount of work in the gymnasium by lifting a 33 kg mass. How many times must he raise the mass to expend this amount of energy? Assume that he raises it a distance of 2 m each time and that he regains no energy when it is dropped to the floor. The acceleration of gravity is 9.8 m/s2 . Answer in units of times.

Answer 1

Solution:

Energy lost in raising the mass = mgh

=> E = 33 x 9.8 x 2

=> E = 646.8 J

=> E = 646.8/4.184

=> E = 154.588 Cal

n = 1533 / 154.588

=> n = 10 times

Thanks