Because of friction, rotational kinetic energy is not conserved while the disks' surfaces slip over each other. what is the final rotational kinetic energy, kf, of the two spinning disks? express the final kinetic energy in terms of it, ir, and the initial kinetic energy ki of the two-disk system. no angular velocities should appear in your answer.

Ultraviolet radiation is dangerous because it has a high enough energy to damage skin cells. what is the best explanation of the relationship between wavelength and wave energy? a) wave energy is related only to frequency, not wavelength. b) longer wavelengths have lower frequencies but higher energy. c) the shorter the wavelength, the lower the frequency and the higher the energy. d) the shorter the wavelength, the higher the frequency and the higher the energy.