Velocity of electrons

  • Thread starter Punch
  • Start date
  • #1
21
0

Homework Statement



A beam of electrons, with kinetic energy of 500eV, enters mid-way into the space between two oppositely charged parallel plates with a potential difference of 100V

Homework Equations



Determine the velocity of the electrons

The Attempt at a Solution



KE=0.5mv^2
500(1.60x10^-19)=0.5(500 x 9.11 x 10^-31)(v^2)
v=5.93x10^5
 

Answers and Replies

  • #2
380
1
First, this isn't really advanced physics, this should be in the introductory physics section.

Second, I have no idea what you did with your equation work. Why is there a 500 term in the mass for the electron? There is only 1 electron, in the beam there may be multiple electrons, but each one carries the same energy.

Also, determine the velocity WHERE? It will be different at different points throughout the apparatus.
 
Last edited:
  • #3
1,137
0
KE=0.5mv^2
500(1.60x10^-19)=0.5(500 x 9.11 x 10^-31)(v^2)
v=5.93x10^5

what is that 500 doing there?

you have just found initial velocity (though it has a small error as i said above)

you also need to calculate the new velocity perpendicular to plates ... which depends on how far electrons have moved b/w the plates.
 

Related Threads on Velocity of electrons

Replies
5
Views
446
  • Last Post
Replies
5
Views
9K
Replies
1
Views
3K
Replies
1
Views
4K
Replies
5
Views
7K
  • Last Post
Replies
5
Views
6K
Replies
3
Views
6K
  • Last Post
Replies
1
Views
2K
Top