00. Biot-Savart's Law and Magnetic Field, Lorentz Force
« First Topic in Next Topic: 01. Amperes Law (∞, Length, Solenoid, Toroid) »
Moving Charges & Magnetism

153320 A long straight wire is carrying a current of 12 A. The magnetic field at a distance of $8 \mathrm{~cm}$ is $\left(\mu_{0}=4 \pi \times 10^{-7} \mathrm{~N} / \mathrm{A}^{2}\right)$.

1 $2 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$
2 $3 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$
3 $4 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$
4 $4 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$
J and K CET-2013
Moving Charges & Magnetism

153321 Two similar coils are kept mutually perpendicular such that their centers coincide. At the centre, find the ratio of the magnetic field through both coils, if the same current is flown

1 $1: \sqrt{2}$
2 $1: 2$
3 $1: 3$
4 $\sqrt{3}: 1$
Manipal UGET-2013
Moving Charges & Magnetism

153323 A magnetic field $B=2 t+4 t^{2}$ (where, $t=$ time) is applied perpendicular to the plane of a circular wire of radius $r$ and resistance $R$. If all the units are in SI the electric charge that flows through the circular wire during $t=0 \mathrm{~s}$ to $t=2 \mathrm{~s}$ is

1 $\frac{6 \pi r^{2}}{\mathrm{R}}$
2 $\frac{20 \pi r^{2}}{R}$
3 $\frac{32 \pi r^{2}}{R}$
4 $\frac{48 \pi r^{2}}{R}$
WB JEE 2013
Moving Charges & Magnetism

153324 A straight wire of length $2 \mathrm{~m}$ carries a current of $10 \mathrm{~A}$. If this wire is placed in a uniform magnetic field of $0.15 \mathrm{~T}$ making an angle of $45^{\circ}$ with the magnetic field, the applied force on the wire will be

1 $1.5 \mathrm{~N}$
2 $3 \mathrm{~N}$
3 $3 \sqrt{2} \mathrm{~N}$
4 $\frac{3}{\sqrt{2}} \mathrm{~N}$
WB JEE 2012
Moving Charges & Magnetism

153325 Current through $A B C$ and $A^{\prime} B^{\prime} C^{\prime}$ is $I$. What is the magnetic field at $P$ ? $B P=P^{\prime}=r$ (Here $C^{\prime} B$ 'PBC are collinear)

1 $\mathrm{B}=\frac{1}{4 \pi} \frac{2 \mathrm{I}}{\mathrm{r}}$
2 $\mathrm{B}=\frac{\mu_{0}}{4 \pi}\left(\frac{2 \mathrm{I}}{\mathrm{r}}\right)$
3 $\mathrm{B}=\frac{\mu_{0}}{4 \pi}\left(\frac{\mathrm{I}}{\mathrm{r}}\right)$
4 zero
WB JEE 2011
Join With Us for More Updates
Moving Charges & Magnetism

153320 A long straight wire is carrying a current of 12 A. The magnetic field at a distance of $8 \mathrm{~cm}$ is $\left(\mu_{0}=4 \pi \times 10^{-7} \mathrm{~N} / \mathrm{A}^{2}\right)$.

1 $2 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$
2 $3 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$
3 $4 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$
4 $4 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$
J and K CET-2013
Moving Charges & Magnetism

153321 Two similar coils are kept mutually perpendicular such that their centers coincide. At the centre, find the ratio of the magnetic field through both coils, if the same current is flown

1 $1: \sqrt{2}$
2 $1: 2$
3 $1: 3$
4 $\sqrt{3}: 1$
Manipal UGET-2013
Moving Charges & Magnetism

153323 A magnetic field $B=2 t+4 t^{2}$ (where, $t=$ time) is applied perpendicular to the plane of a circular wire of radius $r$ and resistance $R$. If all the units are in SI the electric charge that flows through the circular wire during $t=0 \mathrm{~s}$ to $t=2 \mathrm{~s}$ is

1 $\frac{6 \pi r^{2}}{\mathrm{R}}$
2 $\frac{20 \pi r^{2}}{R}$
3 $\frac{32 \pi r^{2}}{R}$
4 $\frac{48 \pi r^{2}}{R}$
WB JEE 2013
Moving Charges & Magnetism

153324 A straight wire of length $2 \mathrm{~m}$ carries a current of $10 \mathrm{~A}$. If this wire is placed in a uniform magnetic field of $0.15 \mathrm{~T}$ making an angle of $45^{\circ}$ with the magnetic field, the applied force on the wire will be

1 $1.5 \mathrm{~N}$
2 $3 \mathrm{~N}$
3 $3 \sqrt{2} \mathrm{~N}$
4 $\frac{3}{\sqrt{2}} \mathrm{~N}$
WB JEE 2012
Moving Charges & Magnetism

153325 Current through $A B C$ and $A^{\prime} B^{\prime} C^{\prime}$ is $I$. What is the magnetic field at $P$ ? $B P=P^{\prime}=r$ (Here $C^{\prime} B$ 'PBC are collinear)

1 $\mathrm{B}=\frac{1}{4 \pi} \frac{2 \mathrm{I}}{\mathrm{r}}$
2 $\mathrm{B}=\frac{\mu_{0}}{4 \pi}\left(\frac{2 \mathrm{I}}{\mathrm{r}}\right)$
3 $\mathrm{B}=\frac{\mu_{0}}{4 \pi}\left(\frac{\mathrm{I}}{\mathrm{r}}\right)$
4 zero
WB JEE 2011
For More Updates join with Us
Moving Charges & Magnetism

153320 A long straight wire is carrying a current of 12 A. The magnetic field at a distance of $8 \mathrm{~cm}$ is $\left(\mu_{0}=4 \pi \times 10^{-7} \mathrm{~N} / \mathrm{A}^{2}\right)$.

1 $2 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$
2 $3 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$
3 $4 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$
4 $4 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$
J and K CET-2013
Moving Charges & Magnetism

153321 Two similar coils are kept mutually perpendicular such that their centers coincide. At the centre, find the ratio of the magnetic field through both coils, if the same current is flown

1 $1: \sqrt{2}$
2 $1: 2$
3 $1: 3$
4 $\sqrt{3}: 1$
Manipal UGET-2013
Moving Charges & Magnetism

153323 A magnetic field $B=2 t+4 t^{2}$ (where, $t=$ time) is applied perpendicular to the plane of a circular wire of radius $r$ and resistance $R$. If all the units are in SI the electric charge that flows through the circular wire during $t=0 \mathrm{~s}$ to $t=2 \mathrm{~s}$ is

1 $\frac{6 \pi r^{2}}{\mathrm{R}}$
2 $\frac{20 \pi r^{2}}{R}$
3 $\frac{32 \pi r^{2}}{R}$
4 $\frac{48 \pi r^{2}}{R}$
WB JEE 2013
Moving Charges & Magnetism

153324 A straight wire of length $2 \mathrm{~m}$ carries a current of $10 \mathrm{~A}$. If this wire is placed in a uniform magnetic field of $0.15 \mathrm{~T}$ making an angle of $45^{\circ}$ with the magnetic field, the applied force on the wire will be

1 $1.5 \mathrm{~N}$
2 $3 \mathrm{~N}$
3 $3 \sqrt{2} \mathrm{~N}$
4 $\frac{3}{\sqrt{2}} \mathrm{~N}$
WB JEE 2012
Moving Charges & Magnetism

153325 Current through $A B C$ and $A^{\prime} B^{\prime} C^{\prime}$ is $I$. What is the magnetic field at $P$ ? $B P=P^{\prime}=r$ (Here $C^{\prime} B$ 'PBC are collinear)

1 $\mathrm{B}=\frac{1}{4 \pi} \frac{2 \mathrm{I}}{\mathrm{r}}$
2 $\mathrm{B}=\frac{\mu_{0}}{4 \pi}\left(\frac{2 \mathrm{I}}{\mathrm{r}}\right)$
3 $\mathrm{B}=\frac{\mu_{0}}{4 \pi}\left(\frac{\mathrm{I}}{\mathrm{r}}\right)$
4 zero
WB JEE 2011
NEET DIGITAL LIBRARY
Moving Charges & Magnetism

153320 A long straight wire is carrying a current of 12 A. The magnetic field at a distance of $8 \mathrm{~cm}$ is $\left(\mu_{0}=4 \pi \times 10^{-7} \mathrm{~N} / \mathrm{A}^{2}\right)$.

1 $2 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$
2 $3 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$
3 $4 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$
4 $4 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$
J and K CET-2013
Moving Charges & Magnetism

153321 Two similar coils are kept mutually perpendicular such that their centers coincide. At the centre, find the ratio of the magnetic field through both coils, if the same current is flown

1 $1: \sqrt{2}$
2 $1: 2$
3 $1: 3$
4 $\sqrt{3}: 1$
Manipal UGET-2013
Moving Charges & Magnetism

153323 A magnetic field $B=2 t+4 t^{2}$ (where, $t=$ time) is applied perpendicular to the plane of a circular wire of radius $r$ and resistance $R$. If all the units are in SI the electric charge that flows through the circular wire during $t=0 \mathrm{~s}$ to $t=2 \mathrm{~s}$ is

1 $\frac{6 \pi r^{2}}{\mathrm{R}}$
2 $\frac{20 \pi r^{2}}{R}$
3 $\frac{32 \pi r^{2}}{R}$
4 $\frac{48 \pi r^{2}}{R}$
WB JEE 2013
Moving Charges & Magnetism

153324 A straight wire of length $2 \mathrm{~m}$ carries a current of $10 \mathrm{~A}$. If this wire is placed in a uniform magnetic field of $0.15 \mathrm{~T}$ making an angle of $45^{\circ}$ with the magnetic field, the applied force on the wire will be

1 $1.5 \mathrm{~N}$
2 $3 \mathrm{~N}$
3 $3 \sqrt{2} \mathrm{~N}$
4 $\frac{3}{\sqrt{2}} \mathrm{~N}$
WB JEE 2012
Moving Charges & Magnetism

153325 Current through $A B C$ and $A^{\prime} B^{\prime} C^{\prime}$ is $I$. What is the magnetic field at $P$ ? $B P=P^{\prime}=r$ (Here $C^{\prime} B$ 'PBC are collinear)

1 $\mathrm{B}=\frac{1}{4 \pi} \frac{2 \mathrm{I}}{\mathrm{r}}$
2 $\mathrm{B}=\frac{\mu_{0}}{4 \pi}\left(\frac{2 \mathrm{I}}{\mathrm{r}}\right)$
3 $\mathrm{B}=\frac{\mu_{0}}{4 \pi}\left(\frac{\mathrm{I}}{\mathrm{r}}\right)$
4 zero
WB JEE 2011
Join With Us for More Updates
Moving Charges & Magnetism

153320 A long straight wire is carrying a current of 12 A. The magnetic field at a distance of $8 \mathrm{~cm}$ is $\left(\mu_{0}=4 \pi \times 10^{-7} \mathrm{~N} / \mathrm{A}^{2}\right)$.

1 $2 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$
2 $3 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$
3 $4 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$
4 $4 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$
J and K CET-2013
Moving Charges & Magnetism

153321 Two similar coils are kept mutually perpendicular such that their centers coincide. At the centre, find the ratio of the magnetic field through both coils, if the same current is flown

1 $1: \sqrt{2}$
2 $1: 2$
3 $1: 3$
4 $\sqrt{3}: 1$
Manipal UGET-2013
Moving Charges & Magnetism

153323 A magnetic field $B=2 t+4 t^{2}$ (where, $t=$ time) is applied perpendicular to the plane of a circular wire of radius $r$ and resistance $R$. If all the units are in SI the electric charge that flows through the circular wire during $t=0 \mathrm{~s}$ to $t=2 \mathrm{~s}$ is

1 $\frac{6 \pi r^{2}}{\mathrm{R}}$
2 $\frac{20 \pi r^{2}}{R}$
3 $\frac{32 \pi r^{2}}{R}$
4 $\frac{48 \pi r^{2}}{R}$
WB JEE 2013
Moving Charges & Magnetism

153324 A straight wire of length $2 \mathrm{~m}$ carries a current of $10 \mathrm{~A}$. If this wire is placed in a uniform magnetic field of $0.15 \mathrm{~T}$ making an angle of $45^{\circ}$ with the magnetic field, the applied force on the wire will be

1 $1.5 \mathrm{~N}$
2 $3 \mathrm{~N}$
3 $3 \sqrt{2} \mathrm{~N}$
4 $\frac{3}{\sqrt{2}} \mathrm{~N}$
WB JEE 2012
Moving Charges & Magnetism

153325 Current through $A B C$ and $A^{\prime} B^{\prime} C^{\prime}$ is $I$. What is the magnetic field at $P$ ? $B P=P^{\prime}=r$ (Here $C^{\prime} B$ 'PBC are collinear)

1 $\mathrm{B}=\frac{1}{4 \pi} \frac{2 \mathrm{I}}{\mathrm{r}}$
2 $\mathrm{B}=\frac{\mu_{0}}{4 \pi}\left(\frac{2 \mathrm{I}}{\mathrm{r}}\right)$
3 $\mathrm{B}=\frac{\mu_{0}}{4 \pi}\left(\frac{\mathrm{I}}{\mathrm{r}}\right)$
4 zero
WB JEE 2011