# Capacitors: find the dielectric constant

## Homework Statement

A parallel plate capacitor has a capacitance of 7.8 μF when filled with a dielectric. The area of each plate is 1.5 m^2 and the separation between the plates is 1.3 x 10-5 m. What is the dielectric constant of the dielectric?

## Homework Equations

C= (K(8.85E-12)A)/d

## The Attempt at a Solution

K= (1.5(7.8E-6 F))/((8.85E-12)(1.3E-5)
=1.02E11

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## Homework Statement

A parallel plate capacitor has a capacitance of 7.8 μF when filled with a dielectric. The area of each plate is 1.5 m^2 and the separation between the plates is 1.3 x 10-5 m. What is the dielectric constant of the dielectric?

## Homework Equations

C= (K(8.85E-12)A)/d

## The Attempt at a Solution

K= (1.5(7.8E-6 F))/((8.85E-12)(1.3E-5)
=1.02E11
Your last expression is unclear because the parentheses do not work (I am assuming you forgot a closing parenthesis at the very end). Double check your algebra, it looks like you end up multiplying the capacitance by the area in finding K, which cannot be right.

## Homework Statement

A parallel plate capacitor has a capacitance of 7.8 μF when filled with a dielectric. The area of each plate is 1.5 m^2 and the separation between the plates is 1.3 x 10-5 m. What is the dielectric constant of the dielectric?

## Homework Equations

C= (K(8.85E-12)A)/d

## The Attempt at a Solution

K= (1.5(7.8E-6 F))/((8.85E-12)(1.3E-5)
=1.02E11
I had the area and length switched, thank you