Maximum power when torque is 0 and angular velocity is 0

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The discussion revolves around calculating power for a drill at two specific points where torque and angular velocity are both zero. The equation derived from measurements indicates a linear relationship between axial torque and angular velocity. It is clarified that according to the power formula P = T * ω, if either torque or angular velocity is zero, the power output must also be zero. This leads to the conclusion that the problem may be a trick question, as there are no maxima in a linear equation, confirming that power is indeed zero at those points. The participants agree that the solution aligns with the fundamental principles of physics regarding power and work.
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Homework Statement



What is the power the drill can supply at the two points of interest(The intersections at the axis')

This is a direct translation of the dutch problem. So basically what's going on is we made measurements of the RPM and angular displacement of our mechanical system (irrelevant at this point) We then converted all the points (correctly) into angular velocity (the RPM points) and the angular displacement to axial torque applied. We then used a scatter plot to plot these points (as per instruction) and found an equation for the linear regression (all using MATLAB)

So it boils down to the fact that I have an equation like this:
y= 0.15781x + 155.11

Where y is axial torque as a function of angular velocity.

So to come back to my first point; they are asking for the power at the axis intersections so when there is no moment opposing the motor (maximum angular velocity) and when there is no angular velocity (so maximum moment -> drill stationary)

But how can this even be right? The equation for power is P = T*ω

So when either one is zero the answer is zero but this can't be right can it?

I hope I have explain it thoroughly enough...
 
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P=T*w
when w is close to zero, T will be high since P is roughly constant.
 
Yes but the problem states we have to find the power at both T and w when they are close to 0. How should I got about doing this? This (first post) is all the information available
 
Ignore my earlier post; I wasn't paying attention.

y= 0.15781x + 155.11

When x=0, you can calculate the maximum torque. Since it's not turning, it's doing no work, and because power is rate of doing work, so power=0. :smile:
 
That's what I thought but it can't be THAT easy can it? But I guess it's some sort of a trick question because there are no maxima in a linear equation (which we were supposed to find) so 0 it is!
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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