Which is larger: a megawatt or a kilowatt? how many times larger is it

The air that we breath is made mostly of which gaseous molecule

The magnitude of the poynting vector of a planar electromagnetic wave has an average value of 0.939 w/m^2 . the wave is incident upon a rectangular area, 1.5 m by 2.0 m, at right angles. how much total electromagnetic energy falls on the area during 1.0 minute?

Mechanical energy is when the amount of kinetic and potential energies added together remains the same. conserved created lost