28. consider a large number of hydrogen atoms with electrons randomly distributed in the n = 1, 2, 3, and 4 orbits. (a) how many different wavelengths of light are emitted by these atoms as the electrons fall into lower-energy orbitals? (b) calculate the lowest and highest energies of light produced by the transitions described in part (a). (c) calculate the frequencies and wavelengths of the light produced by the transitions described in part (b).

Explain in physical terms how a microwave oven works. what would happen when you put a conductor in the microwave oven? explain.

Which explanation describes the forces involved for a person to walk down the sidewalk? a. the person's feet push backward on the sidewalk; the sidewalk pushes backward on the person. b. the person's feet push forward on the sidewalk; the sidewalk does not push on the person. c. the person's feet push backward on the sidewalk; the sidewalk pushes forward on the person. d. the person's feet push forward on the sidewalk; the sidewalk pushes forward on the person.

Eddy whose mass is 55kg climbs up the 1.50 meter high stairs in 2s.calculate eddy’s power rating