this is not deeper in metal it is more hghtly bound

This preview shows page 1. Sign up to view the full content.

This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 5 J- m)/(λ m) E= hc/λ = (1240 eV- nm)/(λ nm) Red Photon: 650 nm Ephoton = 1240 eV- nm = 1.91 eV 650 nm Work funcHons of metals (in eV): Aluminum 4.28 eV Cesium 2.1 Lead 4.14 Potassium 2.3 Beryllium 5.0 eV Cobalt 5.0 Magnesium 3.68 Platinum 6.35 Cadmium 4.07 eV Copper 4.7 Mercury 4.5 Selenium 5.11 Calcium Carbon 2.9 4.81 Gold Iron 5.1 4.5 Nickel Niobium 5.01 4.3 Silver Sodium 4.73 2.28 Uranium 3.6 Zinc 4.3 Photoelectric eﬀect experiment: Apply ConservaHon of Energy Energy in = Energy out Energy of photon = energy needed to kick + IniHal KE of electron electron out of metal as exits metal Electron PotenHal Energy Loosely stuck electron, takes least energy to kick out work function (Φ) = energy needed to kick highest electron out of metal Outside metal Inside metal Warning!! This is not deeper in metal It is more Hghtly bound! Tightly stuck, needs more energy to escape 28 Apply ConservaHon of Energy. Energy in = Energy out Energy of photon = energy needed to kick + IniHal KE of electron electron out of metal as exits metal What happens if send in bunch of blue photons? Electron PotenHal Energy Ephoton work function (Φ) Outside metal Photon gives electron “kick of energy”. Inside metal...
View Full Document

This document was uploaded on 02/26/2014 for the course PHYSICS 2130 at Colorado.

Ask a homework question - tutors are online