Question

A long, straight wire carrying a current of 1.0 A. is placed horizontally in a uniform magnetic field $B=1.0\times {10}^{-5}T$ pointing vertically upward (figure 35-E1). Find the magnitude of the resultant magnetic field at the points P and Q, both situated at a distance of 2.0 cm from the wire in the same horizontal plane.

Answer 1

Given that uniform magnetic field,

$B=1.0\times {10}^{-5}T$

(Pointing vertically upward)

So net magnetic field at point P

$B^{\prime }=2\times 1.0\times {10}^{-5}T$

=$20\mu T$

Net magnetic field at Q

$B"=0$