Answer to Question #178564 in Physics for Adekunle Demilade

Question

A student eats a dinner containing 8.0x10 raised to power 6j of energy. He wishes to do an equivalent amount of work in a nearby gym by lifting a 60kg object.

How many times must he raise the object to expand this much energy? Assume that he raises it a distance of 2.0m each time.

Answer 1

$$W=mghn,$$ $$n=\dfrac{W}{mgh}=\dfrac{8\cdot10^6\ J}{60\ kg\cdot9.8\ \dfrac{m}{s^2}\cdot2\ m}=6800\ times.$$