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

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A shaft rotating at 3000 RPM is transmitting 10,000 watts of power, and the goal is to find the size of the driving couple. The calculations involve using the relationship between power, torque, and angular velocity. An initial attempt yielded an incorrect torque value of 9.54 Nm, while the correct answer is 32 Nm. The error stemmed from a miscalculation in the division involving π. Ultimately, the correct reasoning was present, but a simple calculator mistake led to the confusion.
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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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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...
 

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