Lucy needs to lift a crate to a shelf 20 m high. she does 12,000 j of work on a machine to her. the machine exerts a force of 500 n to lift the crate. what is the efficiency of the machine?
a. 4.2%
b. 24%
c. 58%
d. 83%

Efficiency %

So option (D) will be correct answer

Explanation:

We have given Lucy needs to lift a crate to a shelf

20 m high

Work done by lucky on machine = 12000 J

Force exerted by machine F = 500 N

Distance d = 20 m

So work done by machine

So efficiency %

So option (D) will be correct answer

i think if it were me i whould divide 300 dide 15

step-by-step explanation:

massxgravity x heght=weightxheight= pe

4900=490xh

h=10