06. Magnetic Dipole and Magnetic Moment Due to Current
Moving Charges & Magnetism

153924 Two short bar magnets $A$ and $B$ are arranged coaxially. The distance between their centers is $\mathbf{3 0}$ cm. A compass needle placed on their axis at a distance of $6 \mathrm{~cm}$ from $B$ shows no deflection. The ratio of the magnetic moments of $A$ and $B$ is

1 $16: 1$
2 $1: 16$
3 $64: 1$
4 $1: 64$
Moving Charges & Magnetism

153925 A regular hexagon of side a. A wire of length 24a is coiled on that hexagon. If current in hexagon is $I$, then find the magnetic moment.

1 $6 \sqrt{3} \mathrm{Ia}^{2}$
2 $3 \sqrt{3} \mathrm{Ia}^{2}$
3 $\frac{3 \sqrt{3}}{2} \mathrm{Is}^{2}$
4 $6 \mathrm{Ia}^{2}$
Moving Charges & Magnetism

153926 A moving coil galvanometer has a rectangular wire coil of enclosed area $0.001 \mathrm{~m}^{2}$ and 500 turns. The coil operates in a radial magnetic field of $0.2 \mathrm{~T}$ and carries a current of $6 \pi \times 10^{-8} \mathrm{~A}$. If the torsional spring constant is $6 \times 10^{-7} \mathrm{~N}-\mathrm{m} / \mathrm{rad}$, then the angular deflection of the coil in radians is

1 $\frac{\pi}{100}$
2 $\frac{\pi}{200}$
3 $\frac{\pi}{300}$
4 $\frac{\pi}{400}$
Moving Charges & Magnetism

153927 The magnetic field in a travelling electromagnetic wave has a peak value of 20nT. The peak value of electric field strength is

1 $3 \mathrm{~V} / \mathrm{m}$
2 $6 \mathrm{~V} / \mathrm{m}$
3 $9 \mathrm{~V} / \mathrm{m}$
4 $12 \mathrm{~V} / \mathrm{m}$
Moving Charges & Magnetism

153928 A coil in the shape of an equilateral triangle of side $l$ is suspended between two pole pieces of a permanent magnet, such that magnetic field, $B$ is in plane of the coil. If due to a current $I$ in the triangle, a torque $\tau$ acts on it, the side $l$ of the triangle is -

1 $2\left(\frac{\tau}{\sqrt{3} \mathrm{BI}}\right)^{1 / 2}$
2 $\frac{2}{\sqrt{3}}\left(\frac{\tau}{\mathrm{BI}}\right)$
3 $2\left(\frac{\tau}{\mathrm{BI}}\right)^{1 / 2}$
4 $\frac{1}{\sqrt{3}} \frac{\tau}{\mathrm{BI}}$
Moving Charges & Magnetism

153924 Two short bar magnets $A$ and $B$ are arranged coaxially. The distance between their centers is $\mathbf{3 0}$ cm. A compass needle placed on their axis at a distance of $6 \mathrm{~cm}$ from $B$ shows no deflection. The ratio of the magnetic moments of $A$ and $B$ is

1 $16: 1$
2 $1: 16$
3 $64: 1$
4 $1: 64$
Moving Charges & Magnetism

153925 A regular hexagon of side a. A wire of length 24a is coiled on that hexagon. If current in hexagon is $I$, then find the magnetic moment.

1 $6 \sqrt{3} \mathrm{Ia}^{2}$
2 $3 \sqrt{3} \mathrm{Ia}^{2}$
3 $\frac{3 \sqrt{3}}{2} \mathrm{Is}^{2}$
4 $6 \mathrm{Ia}^{2}$
Moving Charges & Magnetism

153926 A moving coil galvanometer has a rectangular wire coil of enclosed area $0.001 \mathrm{~m}^{2}$ and 500 turns. The coil operates in a radial magnetic field of $0.2 \mathrm{~T}$ and carries a current of $6 \pi \times 10^{-8} \mathrm{~A}$. If the torsional spring constant is $6 \times 10^{-7} \mathrm{~N}-\mathrm{m} / \mathrm{rad}$, then the angular deflection of the coil in radians is

1 $\frac{\pi}{100}$
2 $\frac{\pi}{200}$
3 $\frac{\pi}{300}$
4 $\frac{\pi}{400}$
Moving Charges & Magnetism

153927 The magnetic field in a travelling electromagnetic wave has a peak value of 20nT. The peak value of electric field strength is

1 $3 \mathrm{~V} / \mathrm{m}$
2 $6 \mathrm{~V} / \mathrm{m}$
3 $9 \mathrm{~V} / \mathrm{m}$
4 $12 \mathrm{~V} / \mathrm{m}$
Moving Charges & Magnetism

153928 A coil in the shape of an equilateral triangle of side $l$ is suspended between two pole pieces of a permanent magnet, such that magnetic field, $B$ is in plane of the coil. If due to a current $I$ in the triangle, a torque $\tau$ acts on it, the side $l$ of the triangle is -

1 $2\left(\frac{\tau}{\sqrt{3} \mathrm{BI}}\right)^{1 / 2}$
2 $\frac{2}{\sqrt{3}}\left(\frac{\tau}{\mathrm{BI}}\right)$
3 $2\left(\frac{\tau}{\mathrm{BI}}\right)^{1 / 2}$
4 $\frac{1}{\sqrt{3}} \frac{\tau}{\mathrm{BI}}$
Moving Charges & Magnetism

153924 Two short bar magnets $A$ and $B$ are arranged coaxially. The distance between their centers is $\mathbf{3 0}$ cm. A compass needle placed on their axis at a distance of $6 \mathrm{~cm}$ from $B$ shows no deflection. The ratio of the magnetic moments of $A$ and $B$ is

1 $16: 1$
2 $1: 16$
3 $64: 1$
4 $1: 64$
Moving Charges & Magnetism

153925 A regular hexagon of side a. A wire of length 24a is coiled on that hexagon. If current in hexagon is $I$, then find the magnetic moment.

1 $6 \sqrt{3} \mathrm{Ia}^{2}$
2 $3 \sqrt{3} \mathrm{Ia}^{2}$
3 $\frac{3 \sqrt{3}}{2} \mathrm{Is}^{2}$
4 $6 \mathrm{Ia}^{2}$
Moving Charges & Magnetism

153926 A moving coil galvanometer has a rectangular wire coil of enclosed area $0.001 \mathrm{~m}^{2}$ and 500 turns. The coil operates in a radial magnetic field of $0.2 \mathrm{~T}$ and carries a current of $6 \pi \times 10^{-8} \mathrm{~A}$. If the torsional spring constant is $6 \times 10^{-7} \mathrm{~N}-\mathrm{m} / \mathrm{rad}$, then the angular deflection of the coil in radians is

1 $\frac{\pi}{100}$
2 $\frac{\pi}{200}$
3 $\frac{\pi}{300}$
4 $\frac{\pi}{400}$
Moving Charges & Magnetism

153927 The magnetic field in a travelling electromagnetic wave has a peak value of 20nT. The peak value of electric field strength is

1 $3 \mathrm{~V} / \mathrm{m}$
2 $6 \mathrm{~V} / \mathrm{m}$
3 $9 \mathrm{~V} / \mathrm{m}$
4 $12 \mathrm{~V} / \mathrm{m}$
Moving Charges & Magnetism

153928 A coil in the shape of an equilateral triangle of side $l$ is suspended between two pole pieces of a permanent magnet, such that magnetic field, $B$ is in plane of the coil. If due to a current $I$ in the triangle, a torque $\tau$ acts on it, the side $l$ of the triangle is -

1 $2\left(\frac{\tau}{\sqrt{3} \mathrm{BI}}\right)^{1 / 2}$
2 $\frac{2}{\sqrt{3}}\left(\frac{\tau}{\mathrm{BI}}\right)$
3 $2\left(\frac{\tau}{\mathrm{BI}}\right)^{1 / 2}$
4 $\frac{1}{\sqrt{3}} \frac{\tau}{\mathrm{BI}}$
NEET Test Series from KOTA - 10 Papers In MS WORD WhatsApp Here
Moving Charges & Magnetism

153924 Two short bar magnets $A$ and $B$ are arranged coaxially. The distance between their centers is $\mathbf{3 0}$ cm. A compass needle placed on their axis at a distance of $6 \mathrm{~cm}$ from $B$ shows no deflection. The ratio of the magnetic moments of $A$ and $B$ is

1 $16: 1$
2 $1: 16$
3 $64: 1$
4 $1: 64$
Moving Charges & Magnetism

153925 A regular hexagon of side a. A wire of length 24a is coiled on that hexagon. If current in hexagon is $I$, then find the magnetic moment.

1 $6 \sqrt{3} \mathrm{Ia}^{2}$
2 $3 \sqrt{3} \mathrm{Ia}^{2}$
3 $\frac{3 \sqrt{3}}{2} \mathrm{Is}^{2}$
4 $6 \mathrm{Ia}^{2}$
Moving Charges & Magnetism

153926 A moving coil galvanometer has a rectangular wire coil of enclosed area $0.001 \mathrm{~m}^{2}$ and 500 turns. The coil operates in a radial magnetic field of $0.2 \mathrm{~T}$ and carries a current of $6 \pi \times 10^{-8} \mathrm{~A}$. If the torsional spring constant is $6 \times 10^{-7} \mathrm{~N}-\mathrm{m} / \mathrm{rad}$, then the angular deflection of the coil in radians is

1 $\frac{\pi}{100}$
2 $\frac{\pi}{200}$
3 $\frac{\pi}{300}$
4 $\frac{\pi}{400}$
Moving Charges & Magnetism

153927 The magnetic field in a travelling electromagnetic wave has a peak value of 20nT. The peak value of electric field strength is

1 $3 \mathrm{~V} / \mathrm{m}$
2 $6 \mathrm{~V} / \mathrm{m}$
3 $9 \mathrm{~V} / \mathrm{m}$
4 $12 \mathrm{~V} / \mathrm{m}$
Moving Charges & Magnetism

153928 A coil in the shape of an equilateral triangle of side $l$ is suspended between two pole pieces of a permanent magnet, such that magnetic field, $B$ is in plane of the coil. If due to a current $I$ in the triangle, a torque $\tau$ acts on it, the side $l$ of the triangle is -

1 $2\left(\frac{\tau}{\sqrt{3} \mathrm{BI}}\right)^{1 / 2}$
2 $\frac{2}{\sqrt{3}}\left(\frac{\tau}{\mathrm{BI}}\right)$
3 $2\left(\frac{\tau}{\mathrm{BI}}\right)^{1 / 2}$
4 $\frac{1}{\sqrt{3}} \frac{\tau}{\mathrm{BI}}$
Moving Charges & Magnetism

153924 Two short bar magnets $A$ and $B$ are arranged coaxially. The distance between their centers is $\mathbf{3 0}$ cm. A compass needle placed on their axis at a distance of $6 \mathrm{~cm}$ from $B$ shows no deflection. The ratio of the magnetic moments of $A$ and $B$ is

1 $16: 1$
2 $1: 16$
3 $64: 1$
4 $1: 64$
Moving Charges & Magnetism

153925 A regular hexagon of side a. A wire of length 24a is coiled on that hexagon. If current in hexagon is $I$, then find the magnetic moment.

1 $6 \sqrt{3} \mathrm{Ia}^{2}$
2 $3 \sqrt{3} \mathrm{Ia}^{2}$
3 $\frac{3 \sqrt{3}}{2} \mathrm{Is}^{2}$
4 $6 \mathrm{Ia}^{2}$
Moving Charges & Magnetism

153926 A moving coil galvanometer has a rectangular wire coil of enclosed area $0.001 \mathrm{~m}^{2}$ and 500 turns. The coil operates in a radial magnetic field of $0.2 \mathrm{~T}$ and carries a current of $6 \pi \times 10^{-8} \mathrm{~A}$. If the torsional spring constant is $6 \times 10^{-7} \mathrm{~N}-\mathrm{m} / \mathrm{rad}$, then the angular deflection of the coil in radians is

1 $\frac{\pi}{100}$
2 $\frac{\pi}{200}$
3 $\frac{\pi}{300}$
4 $\frac{\pi}{400}$
Moving Charges & Magnetism

153927 The magnetic field in a travelling electromagnetic wave has a peak value of 20nT. The peak value of electric field strength is

1 $3 \mathrm{~V} / \mathrm{m}$
2 $6 \mathrm{~V} / \mathrm{m}$
3 $9 \mathrm{~V} / \mathrm{m}$
4 $12 \mathrm{~V} / \mathrm{m}$
Moving Charges & Magnetism

153928 A coil in the shape of an equilateral triangle of side $l$ is suspended between two pole pieces of a permanent magnet, such that magnetic field, $B$ is in plane of the coil. If due to a current $I$ in the triangle, a torque $\tau$ acts on it, the side $l$ of the triangle is -

1 $2\left(\frac{\tau}{\sqrt{3} \mathrm{BI}}\right)^{1 / 2}$
2 $\frac{2}{\sqrt{3}}\left(\frac{\tau}{\mathrm{BI}}\right)$
3 $2\left(\frac{\tau}{\mathrm{BI}}\right)^{1 / 2}$
4 $\frac{1}{\sqrt{3}} \frac{\tau}{\mathrm{BI}}$