JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
As shown in the figure, a current of \(2\,A\) flowing in an equilateral triangle of side \(4 \sqrt{3}\,cm\). The magnetic field at the centroid \(O\) of the triangle is: (Neglect the effect of earth's magnetic field.)
- A \(4 \sqrt{3} \times 10^{-4} \,T\)
- B \(4 \sqrt{3} \times 10^{-5} \,T\)
- C \(\sqrt{3} \times 10^{-4}\, T\)
- D \(3 \sqrt{3} \times 10^{-5}\,T\)
Answer & Solution
Correct Answer
(D) \(3 \sqrt{3} \times 10^{-5}\,T\)
Step-by-step Solution
Detailed explanation
\(d \tan 60^{\circ}=2 \sqrt{3}\) \(d =2\,cm\) \(B =3 \times \frac{\mu_0 i }{2 \pi d } \sin 60^{\circ}\) \(=3 \times \frac{2 \times 10^{-7} \times 2}{2 \times 10^{-2}} \times \frac{\sqrt{3}}{2}\) \(=3 \sqrt{3} \times 10^{-5}\)
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