Parallel plate capacitor problem

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Apprentice123
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A parallel plate capacitor is formed using a material whose dielectric constant is 3,00 and whose dielectric strength is 2x10^{8} V/m. The capacitance is 0,25x10^{-6}F and the capacitor must withstand a potential difference maximum of 4000V. Find the minimum area of the plates of the capacitor

I have

C = (E. * A * k)/d

How to calculate d ?
 
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Apprentice123 said:
A parallel plate capacitor is formed using a material whose dielectric constant is 3,00 and whose dielectric strength is 2x10^{8} V/m. The capacitance is 0,25x10^{-6}F and the capacitor must withstand a potential difference maximum of 4000V. Find the minimum area of the plates of the capacitor

I have

C = (E. * A * k)/d

How to calculate d ?

How will the dielectric strength constrain the distance separation?

Then solve for A.
 


LowlyPion said:
How will the dielectric strength constrain the distance separation?

Then solve for A.

the dielectric strength (2x10^8 V/m) is the separation of the plates?
 


Apprentice123 said:
the dielectric strength (2x10^8 V/m) is the separation of the plates?

No. That's a property of the material if it was 1 meter thick.

How thick does it need to be to yield a 4000 V rating?
 


LowlyPion said:
No. That's a property of the material if it was 1 meter thick.

How thick does it need to be to yield a 4000 V rating?


V = (q*d)/(E.*A*k)

It is related to d and A again
 


d = 4000 / 2x10^8 = 2x10^{-5}

A = (C*d)/(E.*k) = 1,88x10^{-7}

It is ?
 


Apprentice123 said:
V = (q*d)/(E.*A*k)

It is related to d and A again

Like I said, find d.

For this problem minimum d is the thickness required to provide a 4000 V separation between the plates. That means that with a dielectric strength of 2*108 you need a thickness of 4000/2*108 2*10-5 m.

Then apply that to Area calculation.

Edit: I see you have in your next post. So yes. That looks like the right way to do it.
 


LowlyPion said:
Like I said, find d.

For this problem minimum d is the thickness required to provide a 4000 V separation between the plates. That means that with a dielectric strength of 2*108 you need a thickness of 4000/2*108 2*10-5 m.

Then apply that to Area calculation.

Edit: I see you have in your next post. So yes. That looks like the right way to do it.

Thank you very much!