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

Energy Stored on a Capacitor

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

Homework Statement


Q18. A 20 F capacitor is charged to 200 V. Its stored energy is:
C. 0.4 J


Homework Equations


q = CV
u = .5CV^2


The Attempt at a Solution


I tried plugging in the numbers and got 1.6E6, which isn't even close to the answer. I really don't know where to go with this one. I even went and found an energy calculator online and it came up with the same answer I got. Is stored energy not the potential energy of the capacitor?
 

Answers and Replies

  • #2
alphysicist
Homework Helper
2,238
1
Hi Strawberry,

Are you sure the capacitance wasn't [itex]20 \mbox{ }\mu F[/itex]? Most capacitors that I've dealt with in problems are in that range, and that would also give the answer you are given.
 
  • #3
21
0
I guess the symbol just didn't show up in the .pdf. Thanks again alphysicist, you've cleared up a ton of things for me in the past few weeks.
 
  • #4
alphysicist
Homework Helper
2,238
1
Sure, I'm glad I could help!
 

Related Threads for: Energy Stored on a Capacitor

  • Last Post
Replies
1
Views
4K
  • Last Post
Replies
6
Views
2K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
5
Views
551
  • Last Post
Replies
3
Views
792
  • Last Post
Replies
4
Views
1K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
8
Views
2K
Top