CBSE 2026 · Region 4 · Set 3 · Q28 · 3 marks
Two coils, one of radius $\displaystyle 0.5$ cm having $\displaystyle 10$ turns and the other of radius $\displaystyle 5$ cm having $\displaystyle 50$ turns are placed coaxially in air such that their centres are coincident. Calculate :(a)the magnetic flux through the smaller coil if the larger coil carries a current of $\displaystyle 3$ A, and(b)the mutual inductance of the two coils.
Two coils, one of radius $\displaystyle 0.5$ cm having $\displaystyle 10$ turns and the other of radius $\displaystyle 5$ cm having $\displaystyle 50$ turns are placed coaxially in air such that their centres are coincident. Calculate :
(a)
the magnetic flux through the smaller coil if the larger coil carries a current of $\displaystyle 3$ A, and
(b)
the mutual inductance of the two coils.
Marking-scheme solution
(a)
$\displaystyle \phi_{1}=N_{1} B_{2} A_{1}=N_{1} \times \dfrac{\mu_{0} I_{2}}{2 r_{2}} \times \pi r_{1}^{2} \times N_{2}$
$\displaystyle =\dfrac{10 \times 4 \pi \times 10^{-7} \times 3 \times 3.14 \times 0.5 \times 0.5 \times 10^{-4} \times 50}{2 \times 5 \times 10^{-2}}$
$\displaystyle =14.789 \times 10^{-7} \mathrm{~Wb}$
(b)
$\displaystyle \mathrm{M}_{12}=\dfrac{\phi_{1}}{\mathrm{I}_{2}}=\dfrac{14.789 \times 10^{-7}}{3}$
$\displaystyle =4.92 \times 10^{-7} \mathrm{H}$
Electromagnetic InductionInductanceApplyshort_answermedium
More from Electromagnetic Induction
- Assertion: The mutual inductance between two coils is maximum when the coils are wound on each other. Reason…2024 · asked 3×
- In the process of charging of a capacitor, the current produced between the plates of the capacitor is:2023 · asked 3×
- A vertically held bar magnet is dropped along the axis of a copper ring having a cut as shown in the diagram.…2025 · asked 3×
- The direction of induced current in the loop abc is:2023 · asked 3×
- (i) Define self-inductance of a coil. Derive the expression for the energy required to build up a current I…2025 · asked 3×
- Two coils C 1 and C 2 are placed close to each other. The magnetic flux φ 2 linked with the coil C 2 varies…2023 · asked 3×
- Assertion: Induced emf produced in a coil will be more when the magnetic flux linked with the coil is more.…2026 · asked 3×
- (i) State Lenz's law and explain how this law is a consequence of conservation of energy principle. (ii) A…2025 · asked 3×
CBSE Class 12 Physics past-paper question from the 2026board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.