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View Full Version : HELP cal/g to j/m^2*sec


Unregistered
04-12-2006, 01:45 PM
I Need to compare the energy available from the sun with the energy it takes to evaporate 1 meter of water.
given 598 cal/g I need to convert it to Joules/meter^2*sec so that I can compare and I can not figure out the conversion for this problem.

Robert Fogt
04-16-2006, 02:00 AM
1 cubic meter = 1,000 liters
1,000 liters * 1000 gram/liter = 1,000,000 grams

so 1 cubic meter of water at standard temperature and pressure weighs 1,000,000 grams.

1,000,000 grams * 598 calories/gram = 598,000,000 calories
598,000,000 calorie [I.T.] = 2,503,706,400 joule

The unit you list is joule/meter² second, which I guess is the number of joules of energy the sun gives off every second per square meter of area?? If that is the case you'd need to multiply it by the surface area of the sun and you'd end up with the joules/second.