Physics 2001 JAMB Past Questions - Question 33: When a piece of rectangular glass block is inserted between two parallel plate capacitor, at constant plate area and distance of separation, the capacitance of the capacitor will

Correct Answer

A

Explanation

When you insert a piece of rectangular glass block between two parallel plate capacitors, the capacitance of the capacitor will increase. This increase in capacitance is due to the fact that the glass block has a higher dielectric constant (also known as relative permittivity) than the surrounding air.

The capacitance (C) of a parallel plate capacitor is given by the formula:

C = ε * A / d

Where:
- C is the capacitance of the capacitor.
- ε (epsilon) is the permittivity of the material between the plates.
- A is the area of the plates.
- d is the distance between the plates.

When you insert the glass block between the plates, it effectively increases the permittivity (ε) between the plates because the glass has a higher permittivity compared to air. As a result, the capacitance of the capacitor increases since the permittivity is in the numerator of the capacitance formula. The increase in capacitance is proportional to the relative permittivity of the glass block compared to that of air.

So, by inserting the glass block, the capacitance of the capacitor will increase, assuming the area of the plates and the separation distance remain constant. This is a fundamental principle used in designing capacitors with dielectric materials to increase their capacitance for various applications.