Question

How strong is the electric field between the plates of a 0.60 \mu F air-gap capacitor if they are 3.0 mm apart and each has a charge of 76 \mu C?

Answer 1

Concepts and reason

The concepts used to solve this problem are charge on the capacitor and electric field.

Use the relation between charge on each plate, potential difference, and capacitance to find the expression for potential difference.

Then use the relation between potential difference and electric field to find the expression for electric field

Fundamentals

The electric field is produced between the two plates of the capacitor.

Expression for charge is,

$q=CV $

Here, is the charge, is the capacitance, and is the potential difference.

Expression for the potential difference in terms of electric field is,

Here, is the electric field and is the distance.

Expression for charge is,

$q=CV $

Rearrange the above expression for .

Expression for the potential difference in terms of electric field is,

Substitute for .

Rearrange the above expression for .

Expression for the electric field is,

Substitute for , for , for .

Therefore, the electric field between the plates is .

Ans:

The electric field between the plates is .