Find the size of Driving couple, if given the power?

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alec433lawrid
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Homework Statement


Not really HW, just revision.

A shaft rotating at 3000 revolutions per minute is transmitting power of 10000 watts. find the size of the driving couple.


Homework Equations


Total wrk done by couple = 2.F.r.θ
Work = Torque . θ ( angle of rotation )
Power = work done / time

The Attempt at a Solution



60 seconds = 3000 revolutions
1 second = ?

Ans came to 50

Using ω = 2∏f resulted in ω = 100∏

Power = (Torque . θ)/t where θ/t = ω

Subject of the formula gave me 9.54 as an answer. When it should be 32Nm

What have I done wrong?
 
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welcome to pf!

hi alec433lawrid! welcome to pf! :smile:
alec433lawrid said:
Subject of the formula gave me 9.54 as an answer. When it should be 32Nm

i get 32

how did you get 9.54 ?​
 


Oh wow!, I am such a noob!

Sorry for wasting your time.

I did have the correct answer. ie my reasoning was correct. My calculator skills on the other hand let me down :(

I did 10000 / 100∏
when i should have done 10000 / (100 * ∏ )

It was a stupid mistake...