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This is a question Crap Gadgets

We wanted a monkey butler and bought one off eBay. Imagine our surprise when we found it was just an ordinary monkey with rabies. Worse: It had no butler training at all. Tell us about your duff technology purchases.

Thanks to Moonbadger for the suggestion

(, Thu 29 Sep 2011, 12:51)
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Let's do the maths
USB ports can supply 5v, 0.5A. That's 2.5W.

A typical cup of coffee is 250ml of something with a density of 1kg/l and a specific heat capacity of 4200 J/kgK. Put that together and your cup of coffee has a heat capacity of 1050J/K.

So 2.5W is enough to heat a cup of coffee at around 8.6 degrees C per hour. Since a cup of coffee will cool from around 100 to around 14 in an hour, the best you can hope for is a 10% reduction in temperature drop.

Or as we heat transfer scientists say, "fuck all".
(, Thu 29 Sep 2011, 18:34, 2 replies)
can't see...blinded...by science...

(, Fri 30 Sep 2011, 5:17, closed)
^ this..
Is brilliant.
(, Fri 30 Sep 2011, 16:00, closed)

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