Question 291: Electromagnetic Induction

Question

Self inductance of solenoid is

Accepted Answer

By Faraday's law, $$\mathrm{e}=\frac{\Delta \phi}{\Delta \mathrm{t}}$$
$$\begin{aligned}
& 	herefore \mathrm{i}=\frac{\mathrm{e}}{\mathrm{R}}=\frac{\Delta \phi}{\mathrm{R} \Delta \mathrm{t}} \
& 	herefore(\mathrm{i} \Delta \mathrm{t})=\frac{\Delta \phi}{\mathrm{R}} \quad 	ext{..... (1)}
\end{aligned}$$
But $$\mathrm{i}=\frac{\Delta \mathrm{Q}}{\Delta \mathrm{t}} \quad 	herefore \Delta \mathrm{Q}=\mathrm{i} \Delta \mathrm{t}$$
$$\begin{aligned}
& 	herefore 	ext { From (1), } \Delta Q=\frac{\Delta \phi}{\mathrm{R}} \
& 	herefore \mathrm{Q}=\frac{\Delta \phi}{\mathrm{R}}
\end{aligned}$$

Answer

directly proportional to current flowing through the coil.

Answer

directly proportional to the length.

Answer

directly proportional to its area of cross-section.

Answer

inversely proportional to the area of cross-section.

Electromagnetic Induction

Self inductance of solenoid is

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