Question

A straight wire carries current in vertical upward direction. A point ‘ $P$ ’ lies just east of it at a small distance and another point ‘ $Q$ ’ lies to the west just same distance. The magnetic field at these points :– (consider earth magnetic field)

• A. $B_{P}>B_{Q}$
• B. $B_{P} < B_{Q}$
• C. $B_{P}=B_{Q}$
• D. None

Answer 1

Answer: (A)

Here $B=$ Magnetic field due to wire
$B_{E H}=$ Horizontal component of earth's
magnetic field $\Rightarrow B_{P}>B_{Q}$