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A quarter horse power motor runs at a sp...

A quarter horse power motor runs at a speed of 600 r . p . m . Assuming 40% efficiency the work done by the motor in one rotation will be

A

`7.46` J

B

7400 J

C

`7.46` ergs

D

`74.6`J

Text Solution

Verified by Experts

The correct Answer is:
A
1 H.P = 746 W
H.P of motor = `(1 H.P)/4 = 746/4 = 186.5 W`
Rotation of motor in one second ` = 600/60 = 10 ` r.p.s
40 % power converted in to work done in 10 rotations
W = (74.6)/10 J = 7.46 J
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