38 verified questions · ~42 minutes · answer key checked against the official NTA final key across multiple sources. Text-only questions (diagram-based excluded until they can be shown properly).
An infinitely long wire is charged uniformly with charge density λ and placed in air. The electric field at distance r from the wire will be:
Two point charges (−q) and (+4q) are placed at separation ‘r’. Where should a third charge be placed so that the entire system of charges becomes in equilibrium?
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