Dear All,

John's microwave oven is starting to look like another case of 'hidden
metric'.

That is his oven was designed to be 25�litres, it was built to be 25�litres,
it was tested at 25�litres � and then dumbed down to some odd number of
decimal cub ft for sales purposes.

John should simply assume that it is a 25 litre oven and get on with the
rest of his life. There is absolutely no future in doing conversions
backwards and forwards.

By the way, some years ago, I read the Australian Standard for evaluating
the power of a microwave oven. From memory, it involved placing a beaker
with 200�millilitres of water in the oven and then observing the temperature
of the water after one (or was it two?) minutes. Then, assuming a litre of
water has a mass of a kilogram, calculating the power rating of the oven (in
watts) was quite straight forward. (You also need to know that the specific
heat of water is 4187�J/kgK)

I found it interesting that this standard method was based on the actual
heating of the contents of the oven rather than a calculation of the power
based on the amount of electrical energy supplied.

Cheers,

Pat Naughtin
Geelong, Australia
61 3 5241 2008
[EMAIL PROTECTED]
http://www.metricationmatters.com



on 2004-12-27 09.12, Bill Potts at [EMAIL PROTECTED] wrote:

> David King wrote: "The 0.09 cubic feet figure you quoted is slightly more
> than 25 litres, so I wonder if that was a rough conversion or the figure for
> the external volume?"
> 
> Looks like a bad case of big foot. 0.09 cu. ft. is just over 2.5 L.
> 
> In fact, John had his decimal point in the wrong place and should have said
> 0.9 cubic feet, which is about 25.5 L.
> 
> Bill Potts, CMS
> Roseville, CA
> http://metric1.org [SI Navigator]
> 

Reply via email to