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3 years ago

8

A mechanical device requires 420 J of work to do 230 J of work to lift a crate. What is the efficiency of the device? 190% 0.5%

183% 55%

2 answers:

erastova [34]3 years ago

8 0

Answer:

55%

Explanation:

Delicious77 [7]3 years ago

4 0

power out / power in so 230/420 = 0.547619048 using sigfiges its about .55 or 55%

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Answer:

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A 0.6 kg ball is initially at rest on a frictionless, horizontal surface. It is struck by a 0.4 kg ball initially moving with a

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3 years ago

A long copper rod of diameter 2.0 cm is initially at a uniform temperature of 100°C. It is now exposed to an air stream at 20°C

Lisa [10]

Answer:

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Explanation:

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WE KNOW THAT

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so we have

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