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Re: [Phys-l] swimming



Hi,

Just a few comments.

A student who had been competitive a the national college level in swimming told me that swimmers are faster underwater and there are rules in competition that require swimmers to break the surface at a certain distance across the pool. Different waves are created. The point being that floating higher might not be a benefit.

I think that I have heard from several sources that submarines are faster when they are in deep, rather than being only a couple of hundred feet down.

Thanks
Roger Haar
U of AZ

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Anthony Lapinski wrote:
A curious/brilliant student asked me a random question during my
electricity topic. She wanted to know if it would be easier or harder to
swim in a pool with a more dense liquid (than water). After class, we
reasoned that it would be harder to move, but your hands could provide
more force on the liquid to propel you forward. You would also not sink as
much. With a less dense liquid, it would be easier to push the liquid
back, but the liquid's reaction force would also be less. There would also
be more friction since you would sink more into the water. We imagined
turning off gravity and trying to "swim" in a sea of air and not moving
too far.

After our discussion, we both figured that it would be easier to swim in a
more dense liquid, but we could not do an experiment to prove this.

Any thoughts/demos for this one?

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