The drift speed in a copper wire is 4.08 × 10-5 m/s for a typical electron current. calculate the magnitude of the electric field inside the copper wire. the mobility of mobile electrons in copper is 4.5 × 10-3 (m/s)/(n/c). (note that though the electric field in the wire is very small, it is adequate to push a sizable electron current through the copper wire.)

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.