Heard on the Today programme just now

[vernon]

Well Roger Harrabin had it wrong. One cubic decimetre (dm3) is not the same as one litre.

1litre is in fact 1.000028 dm3. In practice it make little or no difference but they are not the same.

Your assertion is only true at 40 degrees celcius.

 

[Tim Hall]

Your assertion is only true at 40 degrees celcius.

4, surely. (Max density of water, innit).

 

[vernon]

4, surely. (Max density of water, innit).

No. Colly's value was not the maximum density of water. It was the volume of 1 litre of water at 40 degrees Celsius, an entirely different thing and something worth quibbling over.

Furthermore a cubic decimetre is no longer determined by using a litre of water. it is determined by a cube of sides 10cm and is therefore exactly 1000cm so Colly was wrong on more than one count.

 

[CopperBrompton]

The one that still amazes me is Concorde. Part-built in Britain, with engineers working in Imperial units; part-built in France, with engineers working in Metric units. Yet it all married-up perfectly. The potential for cock-ups there had to have been enormous!