# physics

What mechanical work must you do to lift a uniform log that is 3.3m long and has a mass of 100kg from the horizontal to a vertical position? [Hint: Use the work-energy principle.]

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1. the work done is by lifting it up
so you can use mgh
The tricky part here is that you need to consider where the center of gravity is and it would be the center of the log so the COG is lifted half of the total length of the log

100kg x 9.8 N/Kg x 1.65 meters

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