8:35 不知道emission以及radiation差別在哪裡?或是沒有差別? (根據Cambridge Dictionary) emission: the act of sending out gas, heat, light, etc.(氣體、熱量、光線等的)排放,散發,射出 radiation: (1) a form of energy that comes from a nuclear reaction and that can be very dangerous to health(核)輻射 (2) energy from heat or light that you cannot see(光或熱的)輻射(能) 看起來有差別,但我還是會忘記。 然後LASER的命名真神奇,emission以及radiation兩個單字一起用,可能是和光線有關。