試題詳解

47. Which of the following values is closest to the number of photons per second emitted by a 3.2 mW helium-neon laser with a wavelength of 632 nm? (h=6.63 x10^-34 J·S； C=3.0x10⁸m/s)
(A)1.0 x 10¹⁶
(B)6.0 x 10¹⁵
(C)2.0 x 10¹⁵
(D)5.0X10¹⁴
(E)3.0 X 10¹³