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soldi70 [24.7K]

3 years ago

8

A machine designed to stretch a stiff spring uses 1,550 J of energy to stretch the spring. If the work output is 1,200 J, what i

s the machine’s efficiency?

1 answer:

lapo4ka [179]3 years ago

8 0

Answer:

77%

Explanation:

efficiency= work output/work input X 100%

e = 1,200j/ 1,550 j x100%

e = 1,200/1,550= 0.77

e = 0.77 x 100%

e = 77%

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x = (vx)t

4.65 m = (vx)(0.4064 s)

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An automobile engine can produce 153 N · m of torque. Calculate the angular acceleration (in rad/s^2) produced if 85.2% of this

galina1969 [7]

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46.2 rad/s2

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