Tuesday, August 29, 2006

Back Yard Science : The Measure of a Man

Thinking about Johns attempt to lose some weight (See here)
it occured to me that this provides ample opportunity to do attempt some good old fashioned back yard science (well bath tub science).

I've been told that muscle is 22% denser than fat, so if John succeeds in exchanging fat for muscle we should be able to measure a change in his density.

To this end an experiment was devised, beautiful in its elegance and simplicity, thanks go to Craig, John2, Jim1 and John for their input. It only requires that John takes a bath (we don't need to be there), but before entering the bath he ensures that the bath is filled to just below the overflow. He then enters the bath and briefly submerges, displacing a volume of water equal to his own, which then quickly runs down the drain. After the bath he must measure the volume of water he needs to add back to the bath to make it reach the overflow again. Simple!

Myself and Jim1 shall act as controls in the experiment (though clearly not at the same time), as we are not going to attempt to improve ourselves in the near future. Feel free to try this at home. We will be posting various results on the various blogs involved.


jim said...

john has come up with a possible flaw, which is why i suggest we go to the swimming pool. he may not beable to completely submerge himself in the bath. what then... do bits of john and then sum the results?

Mark Norris said...

Ah the joys of experimental science. We shall see, if he won't fit he may have to do some other approach. The pool clearly wont work, even if you had a perfectly still pool he can't submerge himself for long enough for it to settle. Even if he could in a pool say 25x10x1.5m he would only raise the water level by 4mm and that is assuming he was a metre cubed, which he clearly isnt. Then there is the error in measuring the dimensions of the pool.