Current is flowing in a coil of area $$A$$ and number of turns $$N,$$ then magnetic moment of the coil, $$M$$ is equal to
A.
$$NiA$$
B.
$$\frac{{Ni}}{A}$$
C.
$$\frac{{Ni}}{{\sqrt A }}$$
D.
$${N^2}Ai$$
Answer :
$$NiA$$
Solution :
If there are $$N$$ turns in a coil, $$i$$ is the current flowing and $$A$$ is the area of the coil, then magnetic dipole moment or simply magnetic moment of the coil is $$M = NiA$$
As we know when velocity of charged particle entering to magnetic field region is perpendicular to $$B,$$ then it follows circular path.
Releted MCQ Question on Electrostatics and Magnetism >> Magnetic Effect of Current
Releted Question 1
A conducting circular loop of radius $$r$$ carries a constant current $$i.$$ It is placed in a uniform magnetic field $${{\vec B}_0}$$ such that $${{\vec B}_0}$$ is perpendicular to the plane of the loop. The magnetic force acting on the loop is
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A.
proportional to $$2\left( {{{180}^ \circ } - \theta } \right)$$
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