Jet stream<span>ˈjet ˈˌstrēm/</span>noun1.a narrow, variable band of very strong, predominantly westerly air currents encircling the globe several miles above the earth. There are typically two or three jet streams in each of the northern and southern hemispheres.
(credit to google)
The basic unit of energy is a joule. Kill calories measure the energy available in food.
Say you have 60 cubic meters of an ideal gas at a pressure of 200 pascals. You heat the gas until it expands to a volume of 120 cubic meters. How much work does the gas do? All you have to do is plug in the numbers:
The gas does 12,000 joules of work as it expands under constant pressure.