Go to Home Page
You are here
Go to Reference Section
Go to Directories Section
Go to Community Section
Go to Fun Section
Go to Science Store
Go to About PhysLink.com
Club PhysLink
   Not a member yet?
   Get Free Membership
   Username:
   
   Password:
   
    Remember me
   
   Forgot your login?
Top Destinations Menu
 Ask the ExpertsAsk the
Experts

 Physics and Astronomy Departments DirectoryUniversity
Departments

 Discussion ForumsDiscussion
Forums

 Online Chat Online
Chat

 FREE Einstein eCardsEinstein
eGreetings

 PhysLink.com Science eStoreScience
eStore

Community

Chikrii Word2TeX Software

Click here for a free 2-week trial

Become a Sponsor


   Question

What is the amount of energy given off when an electron and a positron anhilalate?

Asked by: Bill Devenport

Answer

Using 9 x 10-31 Kg. as the mass of each particle, and knowing that their combined mass will be totally converted to energy, you can use Einstein's famous E = mc2 (where c = the speed of light in vacuum = 3 x 108 m/sec) to determine the total energy output of the electron/positron annihilation:

E = (mass of electron + mass of positron) x (speed of light in m/sec)2

E = 2 x (9 x 10-31)kg x (9 x 1016)m2/sec2

E = 1.6 x 10-13 kg m2/sec2 = 1.6 x 10-13 Joules

Answered by: Paul Walorski, B.A. Physics, Part-time Physics Instructor


go to the top  
Advertisement:



All rights reserved. © Copyright '1995-'2004 PhysLink.com