Question

A long straight wire carries the current along +ve x-direction. Consider four points in space $A(0,1,0),B(0,1,1),C(1,0,1)$ and $D(1,1,1)$. Which of the pairs will have the same magnitude of magnetic field?

• A. $A$ and $B$
• B. $A$ and $C$
• C. $B$ and $C$
• D. $B$ and $D$

Answer 1

Answer: (B), (D)

$A$ and $C$
$B$ and $D$

Distance of $A$ and $C$ is same from wire.

Hence, magnetic field at $A$ and $C$ is same in magnitude.
Similarly, for points $B$ and $D$.