Question

Two long parallel carry i and 2i current in same direction Magnetic field just between the wires is
B. if 2i current is switched off then magnetic field at the same point is​

Answer 1

Answer:

if 2i current is switched off then magnetic field at the same point is two long parallel carry i and 2i current in same direction magnetic field just between the wires is .

Answer 2

$B=\frac{2Ki}{d}-\frac{2K*2i}{l-d}$

$B=\frac{2Ki}{d}$

Explanation:

Given we have two infinite current carrying wires with currents i and 2i in same direction.

The magnetic field produced by a infinte carrying wire at a distance of r is given by $MF=\frac{2k}{d}$

where d is the distance from the infinite wire and k is given by the relation with magnetic permeability as μ=4πk.

According to flemmings left hand rule,as the currents are moving in same direction the magnetic field due to them will be in opposite directions.

So the magnetic field due to these wires would be ,

$B=\frac{2Ki}{d}-\frac{2K*2i}{l-d}$

where l is considered as the distance between the infinte wires, and d the distance from the i current carrying wire.

Now if 2i is switched off ,

$B=\frac{2Ki}{d}$