This preview shows page 1. Sign up to view the full content.
Unformatted text preview: The energy of one photon is E = h = (6 . 626 1034 J s) (880 10 3 s1 ) = 5 . 83 1028 J / photon Use this value to convert the stated power in watts (Joules/second) to photons/second: 10 3 J / s 5 . 83 1028 J / photon = 1 . 72 10 30 photons / s 2 8 Under favorable circumstances the human eye can detect 1 . 10 18 J of electromagnetic energy. How many 600 nm photons does this represent? It is simplest to get the photon energy Frst in Joules: E = hc = 1240 eV nm 600 nm = 2 . 07 eV = 2 . 07 eV ( 1 . 602 1019 J / eV ) = 3 . 31 1019 J Now the number of photons is just 1 1018 J 3 . 31 1019 J 3 January 23, 2008...
View
Full
Document
This note was uploaded on 02/29/2008 for the course PHYSICS 31 taught by Professor Hickman during the Spring '07 term at Lehigh University .
 Spring '07
 Hickman
 Energy, Kinetic Energy, Light

Click to edit the document details