# PHYSICS.

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5. A motor lifts a 12 kg mass to a height of 15 m at a constant velocity in 3.5 s.
a) Find the power b) If the motor is only 35% efficient find the input energy.

• PHYSICS. -

a) m g h / t

b) answer to a /.35 is power input
that times 3.5 is energy input.

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