Fall 07 Phys 143l HW 9 Solutions

Fall 07 phys 143l hw 9 solutions

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

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Physics 143 Fall Term 2007 HOMEWORK 9 Due: November 12 Problem 1: (BFG Ch.9 Problem 9) Use Eq.(9-37) to evaluate the frequency of the light emitted in a transition between two states: Assume Z=1(Hydrogen) Eq. 937 E Transition from n=2, l=1 to n=1, l=0 state: E 1 1 m c n 2 1 m c 2 13.6eV 1 2 1 1 10.2eV E 2.5 10 Hz We have one electron and one proton, so the reduce mass is: m m 1836 m 0.9995m 1836 1 m m Notice that E m. Therefore the correction is only E E m ~ 0.5 E m which means using m in Eq. 937 is sometimes precise enough. Problem 2: (BFG Ch.9 Problem 11) Find the <r2> for the ground state of hydrogen. Compare your result with <r>2 for the same state. The ground state of hydrogen: x Therefore the average values are: r 4a | x | r r e x e (The integral R 2a / e / r dr dr 3a dx can be found in some integral tables or you can just integrate by parts) r 4a | x | r r dr r e x e dx dr a (Notice of that both integral have the geometrical/integral/Jacobi factor ) P a g e | 13 r And the spread of r r 3a r r r 2.25a 0 Problem 3: (BFG Ch.8 Problem 22) T...
View Full Document

This note was uploaded on 04/27/2008 for the course PHYSICS 143L taught by Professor Scholberg during the Fall '07 term at Duke.

Ask a homework question - tutors are online