ch33-p023

# ch33-p023 - 23. Let f be the fraction of the incident beam...

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

u I c fI c == + () , 1 0 the same as radiation pressure. 23. Let f be the fraction of the incident beam intensity that is reflected. The fraction absorbed is 1 – f . The reflected portion exerts a radiation pressure of 0 2 r f I p c = and the absorbed portion exerts a radiation pressure of p c a = , 1 0 where I 0 is the incident intensity. The factor 2 enters the first expression because the momentum of the reflected portion is reversed. The total radiation pressure is the sum of the two contributions: 00 0 total 2( 1 ) ( 1 ) . ra f If I f I pp p cc + −+ =+= = To relate the intensity and energy density, we consider a tube with length A and cross- sectional area A , lying with its axis along the propagation direction of an electromagnetic
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 06/03/2011 for the course PHY 2049 taught by Professor Any during the Spring '08 term at University of Florida.

Ask a homework question - tutors are online