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Question
Find the dimensions of magnetic permeability \[\mu_0\]
The relevant equation are \[F = qE, F = qvB, \text{ and }B = \frac{\mu_0 I}{2 \pi a};\]
where F is force, q is charge, v is speed, I is current, and a is distance.
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Solution
Magnetic permeability,
\[\mu_0 = \frac{B \times 2\pi r}{I}\]
\[\text{ Here,} \left[ B \right] = {\left[ {MT}^{- 2} A^{- 1} \right]}\text{ and } \left[ r \right] = {\left[ L \right]}\]
\[\text{So, dimension of magnetic permeability,} [ \mu_0 ] = \frac{\left[ {MT}^{- 2} A^{- 1} \right] \times \left[ L \right]}{\left[ A \right]} = \left[ {MLT}^{- 2} A^{- 2} \right]\].
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