Q1 of 106 Page 121

Find the dimensional formula of ϵ0.

We know that,


Electrostatic force,


Where


Єo is the permittivity of vacuum


q1, q2 is the magnitude of the charges on the charge particles


r is the distance between the two charge particles.


Taking the dimensions,



Note that Charge = Current × Time. Hence, its dimensional formula is


Note that 4π is a dimensionless constant. Note that . Hence, . Also, r is just distance or length. Thus,



Rearranging, we get



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