Same chapter3 marksDifficulty: Medium
What is an equipotential surface? State two of its properties.
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3 marksDifficulty: Medium
What is a dielectric, and how does inserting one between the plates of a capacitor change its capacitance?
Original Khojo Papers practice question — not from a past board paper.
Answer
A dielectric is an insulating material that becomes polarised in an electric field. Inserting one between the plates sets up an internal field opposing the applied one, which reduces the net field and the potential difference for the same charge, so the capacitance rises by the factor K, the dielectric constant of the material.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The capacitance becomes Kε0A/d.
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