Find the dimensions of \(\frac{B}{\mu_0}\) (Shift I Memory Based)
Find the dimensions of \(\frac{B}{\mu_0}\) (Shift I Memory Based)
\(\left[{\mathrm{AL}}^{-1}\right]\)
Magnetic field B :
The dimensional formula for B is derived from the Lorentz force law:
\(
F=q v B \quad \Rightarrow \quad B=\frac{F}{q v}
\)
1. Force (F) has the dimensional formula:
\(
[F]=\left[\mathrm{MLT}^{-2}\right]
\)
2. Charge (q) has the dimensional formula:
\(
[q]=[\mathrm{AT}]
\)
3. Velocity (v) has the dimensional formula:
\(
[v]=\left[\mathrm{LT}^{-1}\right]
\)
Thus, the dimensional formula for B is:
\(
[B]=\frac{\left[\mathrm{MLT}^{-2}\right]}{[\mathrm{AT}]\left[\mathrm{LT}^{-1}\right]}=\frac{[\mathrm{M}]\left[\mathrm{T}^{-2}\right]}{[\mathrm{A}]}=[\mathrm{M}]\left[\mathrm{A}^{-1}\right]\left[\mathrm{T}^{-2}\right]
\)
Magnetic permeability ( \(\mu_0\) ):
The dimensional formula of \(\mu_0\) is:
\(
\left[\mu_0\right]=[\mathrm{M}][\mathrm{L}]\left[\mathrm{T}^{-2}\right]\left[\mathrm{A}^{-2}\right]
\)
Dimensions of \(\frac{B}{\mu_0}\) :
Using the formula:
\(
\frac{B}{\mu_0}=\frac{[\mathrm{M}]\left[\mathrm{A}^{-1}\right]\left[\mathrm{T}^{-2}\right]}{[\mathrm{M}][\mathrm{L}]\left[\mathrm{T}^{-2}\right]\left[\mathrm{A}^{-2}\right]}
\)
Cancel the terms:
\(
\frac{B}{\mu_0}=[\mathrm{A}]\left[\mathrm{L}^{-1}\right]
\)
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