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Question:

In terms of basic units of mass(M), length(L), time(T) and charge(Q), the dimensions of magnetic permeability of vacuum (µ₀) would be?

[MLQ⁻²]

[LTQ⁻¹]

[LT⁻¹Q⁻¹]

[ML²T⁻¹Q⁻²]

Solution:

Correct option is A. [MLQ⁻²]
Force acting per unit length of each of two parallel wires carrying currents in the same direction placed certain distance apart in vacuum is
F/l = µ₀/(4π) * 2I₁I₂/r
MLT⁻²/L = µ₀(Q/T)²/L
Therefore, the dimensions of µ₀ are [MLQ⁻²]