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Asked in GUJCET 2026 · Dimensional formula of a named quantity
Given: (B²)/(2μ₀).
Idea: recognise the combination -- it is the energy stored per unit volume in a magnetic field, so work with energy density.
(energy)/(volume)=(M¹L²T⁻²)/(L³)=M¹L⁻¹T⁻², the same set as pressure.
Confirm from the symbols: F=BIℓ gives [B]=M¹L⁰T⁻²A⁻¹, and [μ₀]=M¹L¹T⁻²A⁻².
([B]²)/([μ₀])=(M²L⁰T⁻⁴A⁻²)/(M¹L¹T⁻²A⁻²)=M¹L⁻¹T⁻² -- the current dimension cancels.
So the answer is M¹L⁻¹T⁻²; the 2 in the denominator is a pure number and changes nothing.
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