14.1 The electromagnetic spectrum电子波谱 A wave is usually described in terms of its wavelength(波长λ) or its frequency(频率v The energy of quantum of electromagnetic energy(E)is directly related to its frequency the frequency h . Planck's constant, 6.63 X 10-34JS14.1 The electromagnetic spectrum 电子波谱 A wave is usually described in terms of its wavelength (波长λ ） or its frequency (频率ν) The energy of quantum of electromagnetic energy (E) is directly related to its frequency. ν ----- E = hv the frequency (Hz) h ----- Planck's constant, 6.63 X 10 -34 JS