A motor hoists a 50-kg crate at constant speed to a height of h = 6 m in 3 s. If the indicated power of the motor is 4 kw, determine the motor's efficiency.

A motor hoists a 50-kg crate at constant speed to a height of h = 6 m

1.	A motor hoists a 50-kg crate at constant speed to a height of h = 6 m in 3 s. If the indicated power of the motor is 4 kw, determine the motor's efficiency.
A.	e = 0.025 (2.5%)
B.	e = 0.245 (24.5%)
C.	e = 0.736 (73.6%)
D.	e = 0.05 (5.0%)
Answer» C. e = 0.736 (73.6%)

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A motor hoists a 50-kg crate at constant speed to a height of h = 6 m in 3 s. If the indicated power of the motor is 4 kw, determine the motor's efficiency.

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