Parallel-plate capacitor with circular plates giving wrong answer

[bbbbbev]

Hi. I have this seemingly easy problem that I cannot get the right answer to! Here it is:

A parallel-plate capacitor has circular plates of 6.00 cm radius and 2.00 mm separation.
Calculate the capacitance.

Ok, so I thought the formula for capacitance was [(epsilon)_0 x Area]/distance = capacitance

So I tried: [(8.85E-12 F/m)(4(pi)(0.06m)^2)]/0.002m = 200.2 pF

I cannot figure out what I am doing wrong. That formula is in the book! Am I overlooking something? Thanks in advance for any help you can give!

Beverly

 

[whozum]

The area of a circle isn't 4*pi*r^2. :)

 

[bbbbbev]

Aggh! I'm such an idiot! What was I thinking? Haha, Thanks!