Q121 / 160 · AP EAMCET 2024 (23 May Shift 1) · Physics
Which of the following is not a unit of permeability
- AHenry meter-1
- BWeber ampere ${ }^{-1}$ meter $^{-1}$
- COhm second meter ${ }^{-1}$
- Correct answerDVolt second meter ${ }^{-1}$
Solution
Self inductance, $\mathrm{L}=\frac{\mu_0 \mathrm{~N}^2 \mathrm{~A}}{1}$
$\therefore \quad$ Unit of $\mu_{\mathrm{o}}=\frac{\mathrm{H} \cdot \mathrm{m}}{\mathrm{m}^2}=\mathrm{H} \mathrm{m}^{-1}$
Also, $\mathrm{L}=\frac{\phi}{\mathrm{I}}=\mathrm{WbA}^{-1}$
$\therefore \quad$ Unit of $\mu_{\mathrm{o}}=\frac{\mathrm{WbA}^{-1} \cdot \mathrm{~m}}{\mathrm{~m}^2}=\mathrm{WbA}^{-1} \mathrm{~m}^{-1}$
Also, $\mathrm{L}=\frac{\mathrm{e}}{\frac{\mathrm{dI}}{\mathrm{dt}}}=\frac{\mathrm{V}}{\mathrm{As}^{-1}}=\mathrm{VA}^{-1} \mathrm{~s}=\Omega \mathrm{s}$
$\therefore \quad$ Unit of $\mu_0=\frac{\mathrm{VsA}^{-1} \cdot \mathrm{~m}}{\mathrm{~m}^2}=\mathrm{VsA}^{-1} \mathrm{~m}^{-1}$ $=\frac{\Omega \mathrm{s} \cdot \mathrm{m}}{\mathrm{m}^2}=\Omega \mathrm{sm}^{-1}$
Hence, the correct answer is option: 'D'.