We know that, velocity of light c is terms of ε0 and μ0 is given by c=μ0ε01⇒c2=μ0ε01c2=μ021⋅ε0μ0⇒c=μ01ε0μ0⇒ε0μ0=cμ0 .......(i) Dimension of magnetic field, B=NIAτ=[A][L2][ML2T−2]=[MA−1T−2] Again, B=μ0nI∴μ0=nlB=[L−1][A][MA−1T−2]=[MLA−2T−2]μ0=[MLA−2T−2] .......(ii) and C=[LT−1] .......(iii) From Eqs. (i), (ii) and (iii), we get ε0μ0=[LT−1][MLA−2T−2]=[ML2T−3A−2]