Question

To be rescued from the roof of a burning building, a 82-kg man must be able to jump straight up and catch hold of a rope ladder hanging from a helicopter. He has to raise his center of mass 2.00 m above the roof to do so.

A.

If he crouches down such that his center of mass is 0.50 m above the roof and his feet leave the roof when his center of mass is 1.05 mabove the roof, what minimum force must he exert on the roof to reach the ladder?

B.

A typical candy bar contains about Ecandy = 900 kJ of food energy. How many candy bars does this jump require?

Answer 1