Question

A helicopter, starting from rest, accelerates straight up from the roof of a hospital. The lifting...

A helicopter, starting from rest, accelerates straight up from the roof of a hospital. The lifting force does work in raising the helicopter. An 780-kg helicopter rises from rest to a speed of 8.5 m/s in a time of 5.0 s. During this time it climbs to a height of 9.7 m. What is the average power generated by the lifting force?

Homework Answers

Answer #1

Average power is the work done per unit time, where work done is the sum of change in kinetic energy and change in potential energy.

That is,

where

Mass of the helicopter is

The final speed is

Height reached is

And acceleration due to gravity is

therefore,

then, average power is

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