p38_061

# P38_061 - 5 kV(b Setting this amount of potential energy loss | ∆ U | = 255 5 keV equal to the correct relativistic kinetic energy we

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

61. (a) We assume the electron starts from rest. The classical formula for kinetic energy is Eq. 38-48, so if v = c then this (for an electron) would be 1 2 mc 2 = 1 2 (511 keV) = 255 . 5 keV (using Table 38-3). Setting this equal to the potential energy loss (which is responsible for its acceleration), we Fnd (using Eq. 25-7) V = 255 . 5keV | q | = 255 keV e = 255
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: . 5 kV . (b) Setting this amount of potential energy loss ( | ∆ U | = 255 . 5 keV) equal to the correct relativistic kinetic energy, we obtain (using Eq. 38-49) mc 2 Ã 1 p 1 − ( v/c ) 2 − 1 ! = | ∆ U | = ⇒ v = c s 1 + µ 1 1 − ∆ U/mc 2 ¶ 2 which yields v = 0 . 745 c = 2 . 23 × 10 8 m/s....
View Full Document

## This note was uploaded on 11/12/2011 for the course PHYS 2001 taught by Professor Sprunger during the Fall '08 term at LSU.

Ask a homework question - tutors are online