Two magnets of equal mass are joined at 90 ° each other as shown in figure. Magnet N _ 1 S _ 1 has a magnetic moment 3 times that of N _ 2 S _ 2 . The arrangement is pivoted so that it is free to rotate in horizontal

NTA Abhyas 2020

NTA Abhyas 2020 · Physics · Magnetic Properties of Matter

Two magnets of equal mass are joined at 90 ° each other as shown in...

Two magnets of equal mass are joined at 90

°

each other as shown in figure. Magnet

{N}_{1}{S}_{1}

has a magnetic moment

\sqrt{3} times that of

{N}_{2}{S}_{2}

. The arrangement is pivoted so that it is free to rotate in horizontal plane. When in equilibrium, what angle should

{N}_{1}{S}_{1}

make with magnetic meridian?<br /> <br /> <img alt="" src="/api/proxy-image?url=https%3A%2F%2Ffirebasestorage.googleapis.com%2Fv0%2Fb%2Fquantrexacademy-app.firebasestorage.app%2Fo%2Fquestions%252Ffigs%252Fnta_abhyas%252Fjee_main%252Fimages%252FPhys_28.png%3Falt%3Dmedia \text{ and } clean=1 \text{ and } v=wm2" data-qx-orig-src="https://firebasestorage.googleapis.com/v0/b/quantrexacademy-app.firebasestorage.app/o/questions%2Ffigs%2Fnta_abhyas%2Fjee_main%2Fimages%2FPhys_28.png?alt=media" data-qx-storage-src="https://firebasestorage.googleapis.com/v0/b/quantrexacademy-app.firebasestorage.app/o/questions%2Ffigs%2Fnta_abhyas%2Fjee_main%2Fimages%2FPhys_28.png?alt=media" style="max-width:100%; object-fit:contain" style="width: 120px; height: 120px;" />

C. 30 $°$

In equilibrium, the resultant magnetic moment will be along magnetic meridian. Let

{N}_{1}{S}_{1}

make

&ang;&theta;

with resultant

tan&theta; = \dfrac{{M}_{2}}{{M}_{1}} = \dfrac{M}{\sqrt{3}M} = \dfrac{1}{\sqrt{3}} &there4; &theta; = 30 &deg;