A long straight wire carrying a 4-A current is placed along the x-axis as shown in the figure.What is the magnitude of the magnetic field at a point P,located at y = 2 cm,due to the current in this wire?

Question

Quizplus · Accepted Answer

Using the formula for calculating the magnetic field of a long straight wire,

B = (μ0 I) / (2πr)

where B is the magnetic field, μ0 is the permeability of free space, I is the current, and r is the distance from the wire.

In this case, the distance from the wire (r) is equal to the y-coordinate of point P, which is 2 cm or 0.02 m.

Substituting the given values into the formula, we get:

B = (4π × 10-7 T m/A)(4 A) / (2π(0.02 m))

B = 0.0008 T = 8 × 10-4 T = 8 × 102 μT

Therefore, the magnitude of the magnetic field at point P is 40 μT (option C).

A Long Straight Wire Carrying a 4-A Current Is Placed