Gujarat BoardEnglish MediumSTD 12 SciencePhysicsELECTROMAGNETIC INDUCTION2 Marks
Question
Explain mutual induction using Faraday's two coil experiment. Obtain expression
✓
Answer
$\varepsilon_1=- M \frac{d l_2}{d t}$.
→In the figure, arrangement of two coil experiment is shown. Here, coils $C _1$ and $C _2$ are placed coaxially. →When electric current $I _2$ passing through coil $C _2$ changes, magnetic flux linked with coil $C _1$ changes and hence induced emf $\varepsilon_1$ arises. →When electric current $I _2$ flows through $C _2$, total magnetic flux linked with coil $C _1$ having $N _1$ turns is $N _1 \phi_1 \propto I _2$ $\therefore N _1 \phi_1= M I _2$ Where, M is mutual inductance →For current changing with time, $\frac{d}{d t}\left(N_1 \phi_1\right)= M \frac{d}{d t}\left( I _2\right)$ →According to Faraday's law, induced emf in $C _1$ $\varepsilon_1=-\frac{d}{d t}\left(N_1 \phi_1\right)$ →From equation (2) and (3), $\varepsilon_1=- M \frac{d I _2}{d t}$ →Equation (4) is the required result. →Here, value of induced emf depends on time rate of change of electric current and mutual inductance.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.