Question 253: Magnetism and Matter

Question

If in a circular coil $$A$$ of radius $$R,$$ current $$I$$ is flowing and in another coil $$B$$ of  radius $$2R$$ a current $$2I$$ is flowing, then the ratio of the magnetic fields $${B_A}$$ and $${B_B}$$, produced by them will be

Accepted Answer

KEY CONCEPT :
We know that the magnetic field produced by a current carrying circular coil of radius $$r$$
at its center is $$B = {{{\mu _0}} \over {4\pi }}{I \over r} 	imes 2\pi $$
Here $${B_A} = {{{\mu _0}} \over {4\pi }}{I \over R} 	imes 2\pi $$ and
$${B_B} = {{{\mu _0}} \over {4\pi }}{{2I} \over {2R}} 	imes 2\pi $$
$$ \Rightarrow {{{B_A}} \over {B{}_B}} = 1$$

Answer

$$1$$

Answer

$$2$$

Answer

$$1/2$$

Answer

$$4$$

Magnetism and Matter

If in a circular coil $A of radius R, current I is flowing and in another coil B of radius 2R a current 2I is flowing, then the ratio of the magnetic fields {B_A} and {B_B}$, produced by them will be

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