A long, straight wire is carrying a current of 5.0 A in the direction shown in the figure. The point P is 0.040 m from the wire.
-What is the magnitude of the magnetic field at the point P?

Question

A long, straight wire is carrying a current of 5.0 A in the direction shown in the figure. The point P is 0.040 m from the wire. 
-What is the magnitude of the magnetic field at the point P?

Quizplus · Accepted Answer

Using the formula for the magnitude of the magnetic field at a point due to a current-carrying wire:

B = (μ0/4π) * (I / r)

where B is the magnetic field, μ0 is the permeability of free space (4π × 10^-7 Tm/A), I is the current, and r is the distance from the wire to the point where the magnetic field is being measured.

Substituting the given values, we get:

B = (4π × 10^-7 Tm/A) * (5.0 A / 0.040 m)

B = 2.5 × 10^-5 T

So the best choice is (C) 2.5 × 10^-5 T.

A Long, Straight Wire Is Carrying a Current of 5