What is a capacitor ?

What is capacitor ? And explain capacitance. Give its SI unit.

What is capacitor? Explain its principle.

What is capacitor? Explain its principle.

Net charge on a capacitor is always zero, then what does a capacitor store? Explain.

The capacity of a capacitor becomes 20muF when gap between the capacitor is filled completely by a dielectric slab of k = 4. What is the capacity of a capacitor with air in between the plates?

What are capacitors?