(A) The ring acts as a circular current loop when it rotates.The current $I$ is defined as the rate of flow of charge, $I = \frac{q}{T}$, where $T$ is

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(A) The ring acts as a circular current loop when it rotates.The current $I$ is defined as the rate of flow of charge, $I = \frac{q}{T}$, where $T$ is the time period of one revolution.Since the frequency is $f$, the time period is $T = \frac{1}{f}$.Therefore, the equivalent current is $I = qf$.The magnetic field $B$ at the centre of a circular loop of radius $R$ carrying current $I$ is given by $B = \frac{\mu_0 I}{2R}$.Substituting the value of $I$, we get $B = \frac{\mu_0 (qf)}{2R} = \frac{\mu_0 qf}{2R}$.

Class 12 Physics Moving Charges and Magnetism Biot-Savart's Law and its application

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$A$ thin ring of radius $R$ metre has charge $q$ coulomb uniformly spread on it. The ring rotates about its axis with a constant frequency of $f$ revolution/s. The value of magnetic induction at the centre of the ring in $\text{Wb/m}^2$ is ($\mu_0$ = permeability of free space)

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A
$\frac{\mu_0 qf}{2R}$
B
$\frac{\mu_0 q}{2\pi R}$
C
$\frac{\mu_0 qf}{2\pi R}$
D
$\frac{\mu_0 q\pi}{2fR}$

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Moving Charges and Magnetism

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Biot-Savart's Law and its application

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The magnetic field due to a current-carrying loop of radius $3 \text{ cm}$ at a point on its axis at a distance of $4 \text{ cm}$ from its centre is $54 \mu\text{T}$. Then,the value of the magnetic field at the centre of the loop is: (in $\mu\text{T}$)

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$A$ thin ring of radius $R$ metre has charge $q$ coulomb uniformly spread on it. The ring rotates about its axis with a constant frequency of $f$ revolution/s. The value of magnetic induction at the centre of the ring in $\text{Wb/m}^2$ is ($\mu_0$ = permeability of free space)

Similar Questions

An infinitely long straight conductor is bent into the shape as shown in the figure. It carries a current of $i$ $ampere$ and the radius of the circular loop is $r$ $metre$. Then the magnetic induction at its centre $O$ will be:

$A$ current of $1.5 \, A$ is flowing through an equilateral triangle of side $9 \, cm$. The magnetic field at the centroid of the triangle is (Assume that the current is flowing in the clockwise direction.)

$A$ wire of resistance $R$ is bent in the form of a square of side $a$ as shown in the figure. Find the magnetic induction at the center of the square $O$ due to the current flowing through it.

The magnetic field due to a current-carrying loop of radius $3 \text{ cm}$ at a point on its axis at a distance of $4 \text{ cm}$ from its centre is $54 \mu\text{T}$. Then,the value of the magnetic field at the centre of the loop is: (in $\mu\text{T}$)

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