What is the formula for capacitance of parallel plate capacitor?

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Jasmine Grover

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The formula for the capacitance of a parallel plate capacitor is C = ε0A/d

C = \(\epsilon_0A \over d\)

  • where C is the capacitance in farads (F)
  • ε0 is the permittivity of free space (a constant equal to 8.85 x 10-12 F/m)
  • A is the area of overlap between the two plates in square meters (m2)
  • d is the distance between the plates in meters (m)

Solved Example

Suppose we have a parallel plate capacitor consisting of two metal plates with an area of 0.1 m2 each, and the distance between the plates is 0.001 m. We want to find the capacitance of this capacitor.

Solution: Using the formula for capacitance of a parallel plate capacitor, we have:

C = ε0A/d

  • where ε0 = 8.85 x 10-12 F/m,
  • A = 0.1 m2,
  • d = 0.001 m.

Substituting these values into the formula, we get:

C = (8.85 x 10-12 F/m) x 0.1 m2/0.001 m

Simplifying this expression, we get:

C = 8.85 x 10-10 F

Therefore, the capacitance of the parallel plate capacitor is 8.85 x 10-10 F.

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