• Support PF! Buy your school textbooks, materials and every day products Here!

Determing the kinetic energy of an electron

  • Thread starter Turion
  • Start date
  • #1
143
2

Homework Statement



sxvTCH3.png


Homework Equations





The Attempt at a Solution



KEi + PEi = KEf
2.4 x 10-19 + e(1) = KEf
KEf = 4.002 x 10-19 J

So option c would be correct, right? Thank you in advance.
 

Answers and Replies

  • #2
143
2
b5LwGCD.png


This one is a trick question, right? It would need 0 kinetic energy because the electric field itself would move the electron to the left until it reaches point C.
 
  • #3
143
2
This one doesn't even make sense to me. How can the electron go back to plate D if plate D has the higher voltage?

CA7nl94.png
 
  • #4
3,740
417

Homework Statement



sxvTCH3.png


Homework Equations





The Attempt at a Solution



KEi + PEi = KEf
2.4 x 10-19 + e(1) = KEf
KEf = 4.002 x 10-19 J

So option c would be correct, right? Thank you in advance.
No. The electron is repelled by the negative plate so its KE decreases when it moves from B to A.
And it's easier if you work in eV directly.
The potential difference between B and A is 1 V so the change in potential energy is 1eV.

And I think you are supposed to post one problem per topic.
 

Related Threads on Determing the kinetic energy of an electron

Replies
1
Views
1K
Replies
2
Views
704
Replies
1
Views
904
Replies
4
Views
4K
Replies
1
Views
2K
  • Last Post
Replies
7
Views
71K
Replies
10
Views
2K
Replies
6
Views
9K
Replies
3
Views
3K
Top