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Andrews [41]
3 years ago
5

Lucy needs to lift a crate to a shelf 20 m high. She does 12,000 J of work on a machine to help her. The machine exerts a force

of 500 N to lift the crate.
What is the efficiency of the machine?

4.2%
24%
58%
83%
Chemistry
1 answer:
geniusboy [140]3 years ago
5 0

N=

500x20/12000=

10/12=

5/6=

83%

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