Question

Two wires of infinite length are lying mutually at right angles to each others as shown in figure. Currents of 2A and 1.5A respectively are flowing in them. The value of magnetic induction at point p will be :

• A. $2\times {10}^{-3}N/Am$
• B. $2\times {10}^{-5}N/Am$
• C. zero
• D. $2\times {10}^{-4}N/Am$

Answer 1

Answer: (B)

$2\times {10}^{-5}N/Am$

$B=B_1+B_2$
$=\frac{{\mu }_{0}i}{2\pi x_1}+\frac{{\mu }_{0}i}{2\pi x_2}$
$=\frac{2\times {10}^{-7}\times 2}{4\times {10}^{-2}}+\frac{2\times {10}^{-7}\times 1.5}{3\times {10}^{-2}}$
$=2\times {10}^{-5}N/A-m$