24 verified questions · ~26 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).
Consider a parallel plate capacitor of area A (of each plate) and separation d between the plates. If E is the electric field and ε₀ is the permittivity of free space between the plates, then the potential energy stored in the capacitor is:
What is the relative decrease in focal length of a lens for an increase in optical power by 0.1 D from 2.5 D? ['D' stands for dioptre]
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