Definition of pound force

[Roady]

Homework Statement

prove by physical demonstaration1lbf accelerates 32lbm @ 1ft/s^2. Is there a pic of a classroom experiment proving this?

Relevant Equations

def 1lbf=32lbm*1ft/s^2

I can divide the #'s out, but so what. I want to see 1lbf move 32lbm.

 

[jbriggs444]

I want to see 1lbf move 32lbm.

Are you trying to convince yourself? Or a third party doubter? How direct does the proof need to be?

 

[jbriggs444]

Does it matter? Can you answer the question?

The direct answer is that I know of no picture or video demonstrating a 32 pound weight being accelerated at 1 foot per second per second by a 1 pound force.

Given the available coefficients of friction, the best demonstration that I can think of would involve something like a pendulum bob on a long wire.

Do you know of a friggn experiment? I'm getting the most inane answers from respondants here; another:can you see your mistake?

Did I speak of your mistake or even imply that you'd made one? In this thread you have not made any mistakes. Up until now, you'd only asked a question.

Duh, if I could I wouldn't ask for help.

Here at physicsforums.com we help people help themselves. That means guiding people to an understanding. Not simply answering questions.

1lbf=m*g, what is that mass is another angle? 1lbf=32lbm*1f/s^2=1lbm*32/s^2, but this product is 32lbm*ft/s^2, so that has to account for something if it's not a pound force.

It sounds like you are trying to argue rather than to understand. And since you have another thread open on this same subject, I will stop responding here.

I will say that $F=ma$ only works in coherent systems of units. More generally the formula is $F=kma$ where $k$ is a unit conversion factor. The U.S. customary system is not coherent. In the U.S. system with pounds force, pounds mass and feet per second squared, $F = \frac{1}{32}ma$

 

[berkeman]

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