The efficiency of a squeaky pulley system is 73 percent. The pulleys are used to raise a mass to a certain height. What force is exerted on the machine if a rope is pulled 18.0 m in order to raise a 58 kg mass a height of 3.0 m

129.9 m

Explanation:

Efficiency is the ratio of work output to work input, expressed as a percentage.

We know that work= mgh hence to get the work input

Work done by applied force=Fd

Fd=2338.273973 J

we have d as 18 m hence

0.55x745.7j and a calculator

another example of kinetic energy would be,

kinetic energy   >     moving energy

answer   >   letter choice (c),   a hammer falling off a table.

hope that !                                         : )