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By what primary heat transfer mechanism does the sun warm the earth?

The nuclear potential that binds protons and neutrons in the nucleus of an atom is often approximated by a square well. imagine a proton conned in an innite square well of length 105 nm, a typical nuclear diameter. calculate the wavelength and energy associated with the photon that is emitted when the proton undergoes a transition from the rst excited state (n 2) to the ground state (n 1). in what region of the electromagnetic spectrum does this wavelength belong?

Acamcorder has a power rating of 20 watts. if the output voltage from its battery is 9 volts, what current does it use?