Re: Physics puzzle: chin-ups.
 

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people who are very thin can often do many chin-ups but not curl very much.

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youre a genius.

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True, but irrelevant.

Re: Physics puzzle: chin-ups.
 

I'm gonna say 40 lb dumbbells bob.

Re: Physics puzzle: chin-ups.
 

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Suppose I weigh 200 pounds and can perform a set of 10 chin-ups. What weight of dumbell should you expect me to be able to curl 10 times?

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Impossible to know.

Re: Physics puzzle: chin-ups.
 

This is a biology problem, not a physics problem.

Re: Physics puzzle: chin-ups.
 

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Impossible to know.

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Really?

Suppose I have an accident and my biceps are cut. Do you think I could still do a chin-up? I hope not. Ok, what if this reduced the strength of my biceps to 10 pounds maximum? 20?

Ok, when you do a chin-up, focus on your biceps. How much does it feel like you are curling? Why? (The answer to the why is basic physics.)

These are the types of things I expect people to think through before posting. If you can't be bothered to think about it, why post?

Re: Physics puzzle: chin-ups.
 

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Impossible to know.

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Really?

Suppose I have an accident and my biceps are cut. Do you think I could still do a chin-up? I hope not. Ok, what if this reduced the strength of my biceps to 10 pounds maximum? 20?

Ok, when you do a chin-up, focus on your biceps. How much does it feel like you are curling? Why? (The answer to the why is basic physics.)

These are the types of things I expect people to think through before posting. If you can't be bothered to think about it, why post?

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there simply isnt enough info to make an accurate guess.

Re: Physics puzzle: chin-ups.
 

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If you see that someone can't quite curl 75 pounds, is it safe to bet that he can't do a 1-handed chin-up?

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Nope. I can do a one handed chin-up, but I'm not even close to curling 75 pounds (with one hand at least). More like 50 for a 1-rep max when I'm in good shape.

As for your problem, it seems impossible to measure accurately. There are too many factors, one of which is how proficient the individual lifter is at the chin-up versus the curl. This fact throws off your whole study, since it is dependent on the subject. You might be able to figure out some reasonable range, however. To do that would probably take experiments, though. This cannot be determined conceptually.

Re: Physics puzzle: chin-ups.
 

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This cannot be determined conceptually.

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He isn't looking for some kind of rigorous proof of an exact number which doesn't even necessarily exist. I would assume he's looking for some kind of argument, based on some reasonable physical assumptions, to make an educated guess. This kind of thing is interesting in its own right.

pzhon, it's an interesting question. I'll think about it for a bit.

Re: Physics puzzle: chin-ups.
 

the title is hilarious.

and im sure there is a correlation between the two with a pretty large variance, but its not even close to a physics "puzzle." lol

Re: Physics puzzle: chin-ups.
 

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and im sure there is a correlation between the two with a pretty large variance, but its not even close to a physics "puzzle." lol

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I don't do this all too often, but I'm going to pull rank on you here. Just because this isn't a textbook problem with a clear cut answer doesn't mean it's not an interesting question. (In reality, textbook problems with clear cut answers are usually the least interesting questions.) pzhon is a mathematician. I'm a physicist. We both seem to think that it is an interesting question. Perhaps that should be given some weight in this instance.