Same chapter3 marksDifficulty: Medium
A circular coil of 100 turns and radius 0.1 m carries a current of 2 A. Find the magnetic field at its centre. Take μ0 = 4π × 10−7 T m A−1.
Magnetic Effects of Current and Magnetism
3 marksDifficulty: Medium
State the Biot-Savart law and Ampere's circuital law.
Original Khojo Papers practice question — not from a past board paper.
Answer
The Biot-Savart law gives the magnetic field due to a small current element as dB = (μ0/4π)(I dl sin θ)/r2, directed perpendicular to the plane of the element and the point. Ampere's circuital law states that the line integral of the magnetic field round a closed loop equals μ0 times the current enclosed by it.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Ampere's law is the magnetic counterpart of Gauss's theorem and is far quicker for symmetric arrangements.
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