h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

There is a strange an illogical thing that occurs in this house with regard to a standard old fashioned bathroom scale and fitted carpet.
When I weigh myself on them on a tiled floor it reads 12.10st (my true weight) but if I put the scales on the carpet the weight reported goes up to 14.3 - how does the extra weight come about then?

Maybe your bathroom is in a time warp where normal laws of physics do not apply. Try watching old startrek programs they have helped me a lot.

Aha the carpet conundrum.

If you buy a 'Weightwatchers' electronic blubber detector(as i did today) it actually comes with little plastic feet that you put on it if you're using it on carpet, and this will solve your problem.

It said i was 13st 5lbs, i said it was a lying ********* ,and that it was both redundant and homeless.

ok...try this :

Place a piece of plywood under the scale and try measuring your weight, first on the carpet, then on the tiled floor (still with the plywood) to see if there is a difference.

Also...how deep is the carpet pile??

alec.

The carpet pile is about 5mm plus another 5mm underlay.
However the conundrum is that the total energy going in (my mass accelerated by gravity) is the same and is being directed into deforming a calibrated spring in the scales. How can this spring be deformed _more_ when put on a carpet than on a solid floor?

I think it is due to the floor actually being a bit springy itself, due to the carpet. How long do you actually stand on the weight? I think it might have to do with the spring/weight system taking a longer time to settle. So if you were to manage to stand still for a while in both places, the end result would be the same weight.

http://www.newscientist.com/article.ns?id=dn2462

This might explain it. If they are simple mechanical scales they would be calibrated on a hard surface. On a hard surface the base of the scales bend more than they would if partially supported by the carpet pile.

Darn. I had hoped it might have been related to the fact that buttered toast is much more likely to fall off your plate over carpet than over lino.

Oh I see - a sort of lipophilic carpet effect .