Time to Lift 50 15.0-kg Boxes at 41.4 W Output

Thread starter mphysicsdc
Start date Mar 20, 2010
Tags

Average Lift Output Power Power output Time

AI Thread Summary

To determine the minimum time required to lift fifty 15.0-kg boxes to a height of 1.88 m with an average power output of 41.4 W, the total energy needed must first be calculated using gravitational potential energy (mgh). The total mass of the boxes is 750 kg, and the energy required to lift them is approximately 14,700 J. Using the power equation P = W/Δt, the time can be derived by rearranging it to Δt = W/P. The discussion highlights the need for clarity on calculating energy and time based on power output. Understanding these calculations is essential for solving the problem effectively.

Mar 20, 2010

mphysicsdc

Homework Statement

If a man has an average useful power output of 41.4 W, what minimum time would it take him to lift fifty 15.0-kg boxes to a height of 1.88 m?

Homework Equations

1/2mv(final)^2 mgy(final) = 1/2mv(initial)^2 mgy(initial)

P=W/Δt

P=Fv

The Attempt at a Solution

Dont even know where to start

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Mar 20, 2010

ideasrule

Homework Helper

How much energy is needed to lift those boxes?

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