A pulley system with 75% efficiency is set up to lift a 21kg bag of nails. The bag is lifted to a height of 2.3m by a person pulling on the rope with a force of 91.5N. What is the work done on the bag of nails by the pulley?

Question

2075 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-04-18T14:46:34

$683.79 J$

Be careful with that bag !!

The person applies a total of $(Mg+91.5 N)$ force. And the displacement is $2.3 m$ .

Hence the work done is:

$(21xx9.8+91.5)Nxx2.3m = 683.79 J$