Solving a Parallel-Plate Capacitor Problem

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The discussion revolves around calculating the capacitance of a parallel-plate capacitor with circular plates. The user initially applies the capacitance formula but incorrectly calculates the area of the circular plates. The correct area formula is πr², not 4πr². After realizing the mistake, the user expresses relief and gratitude for the clarification. The conversation highlights the importance of using the correct geometric formulas in physics calculations.
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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
 
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The area of a circle isn't 4*pi*r^2. :)
 
Aggh! I'm such an idiot! What was I thinking? Haha, Thanks!
 

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