113k views
2 votes
ASAP

A pulley system is used to lift a large piano from the ground floor to the third floor. If 2500 joules of energy was used to move the piano and the work done was 2100 joules, what is the efficiency of the pulley system?
A.
84%
B.
62%
C.
120%
D.
53%

1 Answer

4 votes

Answer:

84%

Step-by-step explanation:

2100 j out / 2500 j in = .84 = 84%

User Bahamut
by
4.9k points