A current 10 A is flowing from east to west in a long straight wire kept on a horizontal table. The magnetic field developed at a distance of 10 cm due north on the table is
The magnetic field due to a straight current-carrying wire is given by
B = μ0I/2πr.
Substituting μ0 4π × 10⁻⁷, I = 10 A and r = 0.1 m, B = 2 × 10⁻⁵ T.
Using the right-hand rule, it acts downwards. Answer: (A).
Share
The magnetic field around a long, straight current-carrying wire is given by Ampere’s circuital law as:
B = μ0I/2πr
.Here:
μ0 4π × 10⁻⁷Tm/A (permeability of free space)
I =10 A (current) r = 0.10m (distance)
Substituting values:
B = 4π × 10⁻⁷× 10/2π × 0.10 = 2 × 10⁻⁵T
To determine the direction of the magnetic field, use the right-hand thumb rule: Point the thumb in the direction of current (east to west) and curl the fingers around the wire. At a point due north, the magnetic field points downward. Hence, the correct answer is:
(A) 2 × 10⁻⁵ T, acting downwards.
For more visit here:
https://www.tiwariacademy.com/ncert-solutions/class-12/physics/chapter-4/