Q19. What is the Stored Energy on a Capacitor Charged to 200 V?

[Strawberry]

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?

 

[alphysicist]

Hi Strawberry,

Are you sure the capacitance wasn't $20 \mbox{ }\mu F$? Most capacitors that I've dealt with in problems are in that range, and that would also give the answer you are given.

 

[Strawberry]

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.

 

[alphysicist]

Sure, I'm glad I could help!