00. Biot-Savart's Law and Magnetic Field, Lorentz Force
Moving Charges & Magnetism

153218 The magnitude of a magnetic field at the centre of a circular coil of radius $R$, having $\mathbf{N}$ turns and carrying a current $I$ can be doubled by changing

1 I to $2 \mathrm{I}$ and $\mathrm{N}$ to $2 \mathrm{~N}$ keeping $\mathrm{R}$ unchanged
2 $\mathrm{N}$ to $\mathrm{N} / 2$ and keeping I and $\mathrm{R}$ unchanged
3 $\mathrm{N}$ to $2 \mathrm{~N}$ and $\mathrm{R}$ to $2 \mathrm{R}$ keeping I unchanged
4 $\mathrm{R}$ to $2 \mathrm{R}$ and I to $2 \mathrm{I}$ keeping $\mathrm{N}$ unchanged
5 1 to $2 \mathrm{I}$ and keeping $\mathrm{N}$ and $\mathrm{R}$ unchanged
Moving Charges & Magnetism

153219 An electron is moving with a velocity $2 \times 10^{6}$ $\mathrm{m} / \mathrm{s}$ along positive $\mathrm{x}$-direction in the uniform electric field of $8 \times 10^{7} \mathrm{~V} / \mathrm{m}$ applied along positive y-direction. The magnitude and direction of a uniform magnetic field (in tesla) that will cause the electrons to move undeviated along its original path is

1 40 in - ve z-direction
2 40 in + ve z-direction
3 4 in + ve $z$-direction
4 4 in - ve z-direction
5 8 in + ve z-direction
Moving Charges & Magnetism

153220 A rectangular conducting loop of length $4 \sqrt{2} \mathrm{~m}$ and breadth $4 \mathrm{~m}$ carrying a current of $5 \mathrm{~A}$ in the anti-clockwise direction is placed in the $x y$ plane. The magnitude of the magnetic induction field vector $B$ at the intersection of the diagonal is $\quad\left(\right.$ use $\mu_{0}=4 \times 10^{-7} \mathrm{NA}^{-2}$ )

1 $1.2 \times 10^{-6} \mathrm{~T}$
2 $1.2 \times 10^{-5} \mathrm{~T}$
3 $2.4 \times 10^{-6} \mathrm{~T}$
4 $2.4 \times 10^{-5} \mathrm{~T}$
5 $1.2 \times 10^{-7} \mathrm{~T}$
Moving Charges & Magnetism

153221 A long straight wire carrying electric current $i$ is bent at its mid-point to form an angle of $45^{\circ}$ as shown in the figure. Magnetic field at a point $P$ at a distance $d$ from the point $Q$ of bending is

1 $\frac{\mu_{0} \mathrm{i}}{4 \pi \mathrm{d}}[\sqrt{2}-1]$
2 $\frac{\mu_{0} \mathrm{i}}{2 \pi \mathrm{d}}[\sqrt{2}-1]$
3 $\frac{\mu_{0} \mathrm{i}}{4 \pi \mathrm{d}}$
4 $\frac{\mu_{0} \mathrm{i}}{2 \pi \mathrm{d}}$
NEET Test Series from KOTA - 10 Papers In MS WORD WhatsApp Here
Moving Charges & Magnetism

153218 The magnitude of a magnetic field at the centre of a circular coil of radius $R$, having $\mathbf{N}$ turns and carrying a current $I$ can be doubled by changing

1 I to $2 \mathrm{I}$ and $\mathrm{N}$ to $2 \mathrm{~N}$ keeping $\mathrm{R}$ unchanged
2 $\mathrm{N}$ to $\mathrm{N} / 2$ and keeping I and $\mathrm{R}$ unchanged
3 $\mathrm{N}$ to $2 \mathrm{~N}$ and $\mathrm{R}$ to $2 \mathrm{R}$ keeping I unchanged
4 $\mathrm{R}$ to $2 \mathrm{R}$ and I to $2 \mathrm{I}$ keeping $\mathrm{N}$ unchanged
5 1 to $2 \mathrm{I}$ and keeping $\mathrm{N}$ and $\mathrm{R}$ unchanged
Moving Charges & Magnetism

153219 An electron is moving with a velocity $2 \times 10^{6}$ $\mathrm{m} / \mathrm{s}$ along positive $\mathrm{x}$-direction in the uniform electric field of $8 \times 10^{7} \mathrm{~V} / \mathrm{m}$ applied along positive y-direction. The magnitude and direction of a uniform magnetic field (in tesla) that will cause the electrons to move undeviated along its original path is

1 40 in - ve z-direction
2 40 in + ve z-direction
3 4 in + ve $z$-direction
4 4 in - ve z-direction
5 8 in + ve z-direction
Moving Charges & Magnetism

153220 A rectangular conducting loop of length $4 \sqrt{2} \mathrm{~m}$ and breadth $4 \mathrm{~m}$ carrying a current of $5 \mathrm{~A}$ in the anti-clockwise direction is placed in the $x y$ plane. The magnitude of the magnetic induction field vector $B$ at the intersection of the diagonal is $\quad\left(\right.$ use $\mu_{0}=4 \times 10^{-7} \mathrm{NA}^{-2}$ )

1 $1.2 \times 10^{-6} \mathrm{~T}$
2 $1.2 \times 10^{-5} \mathrm{~T}$
3 $2.4 \times 10^{-6} \mathrm{~T}$
4 $2.4 \times 10^{-5} \mathrm{~T}$
5 $1.2 \times 10^{-7} \mathrm{~T}$
Moving Charges & Magnetism

153221 A long straight wire carrying electric current $i$ is bent at its mid-point to form an angle of $45^{\circ}$ as shown in the figure. Magnetic field at a point $P$ at a distance $d$ from the point $Q$ of bending is

1 $\frac{\mu_{0} \mathrm{i}}{4 \pi \mathrm{d}}[\sqrt{2}-1]$
2 $\frac{\mu_{0} \mathrm{i}}{2 \pi \mathrm{d}}[\sqrt{2}-1]$
3 $\frac{\mu_{0} \mathrm{i}}{4 \pi \mathrm{d}}$
4 $\frac{\mu_{0} \mathrm{i}}{2 \pi \mathrm{d}}$
Moving Charges & Magnetism

153218 The magnitude of a magnetic field at the centre of a circular coil of radius $R$, having $\mathbf{N}$ turns and carrying a current $I$ can be doubled by changing

1 I to $2 \mathrm{I}$ and $\mathrm{N}$ to $2 \mathrm{~N}$ keeping $\mathrm{R}$ unchanged
2 $\mathrm{N}$ to $\mathrm{N} / 2$ and keeping I and $\mathrm{R}$ unchanged
3 $\mathrm{N}$ to $2 \mathrm{~N}$ and $\mathrm{R}$ to $2 \mathrm{R}$ keeping I unchanged
4 $\mathrm{R}$ to $2 \mathrm{R}$ and I to $2 \mathrm{I}$ keeping $\mathrm{N}$ unchanged
5 1 to $2 \mathrm{I}$ and keeping $\mathrm{N}$ and $\mathrm{R}$ unchanged
Moving Charges & Magnetism

153219 An electron is moving with a velocity $2 \times 10^{6}$ $\mathrm{m} / \mathrm{s}$ along positive $\mathrm{x}$-direction in the uniform electric field of $8 \times 10^{7} \mathrm{~V} / \mathrm{m}$ applied along positive y-direction. The magnitude and direction of a uniform magnetic field (in tesla) that will cause the electrons to move undeviated along its original path is

1 40 in - ve z-direction
2 40 in + ve z-direction
3 4 in + ve $z$-direction
4 4 in - ve z-direction
5 8 in + ve z-direction
Moving Charges & Magnetism

153220 A rectangular conducting loop of length $4 \sqrt{2} \mathrm{~m}$ and breadth $4 \mathrm{~m}$ carrying a current of $5 \mathrm{~A}$ in the anti-clockwise direction is placed in the $x y$ plane. The magnitude of the magnetic induction field vector $B$ at the intersection of the diagonal is $\quad\left(\right.$ use $\mu_{0}=4 \times 10^{-7} \mathrm{NA}^{-2}$ )

1 $1.2 \times 10^{-6} \mathrm{~T}$
2 $1.2 \times 10^{-5} \mathrm{~T}$
3 $2.4 \times 10^{-6} \mathrm{~T}$
4 $2.4 \times 10^{-5} \mathrm{~T}$
5 $1.2 \times 10^{-7} \mathrm{~T}$
Moving Charges & Magnetism

153221 A long straight wire carrying electric current $i$ is bent at its mid-point to form an angle of $45^{\circ}$ as shown in the figure. Magnetic field at a point $P$ at a distance $d$ from the point $Q$ of bending is

1 $\frac{\mu_{0} \mathrm{i}}{4 \pi \mathrm{d}}[\sqrt{2}-1]$
2 $\frac{\mu_{0} \mathrm{i}}{2 \pi \mathrm{d}}[\sqrt{2}-1]$
3 $\frac{\mu_{0} \mathrm{i}}{4 \pi \mathrm{d}}$
4 $\frac{\mu_{0} \mathrm{i}}{2 \pi \mathrm{d}}$
Moving Charges & Magnetism

153218 The magnitude of a magnetic field at the centre of a circular coil of radius $R$, having $\mathbf{N}$ turns and carrying a current $I$ can be doubled by changing

1 I to $2 \mathrm{I}$ and $\mathrm{N}$ to $2 \mathrm{~N}$ keeping $\mathrm{R}$ unchanged
2 $\mathrm{N}$ to $\mathrm{N} / 2$ and keeping I and $\mathrm{R}$ unchanged
3 $\mathrm{N}$ to $2 \mathrm{~N}$ and $\mathrm{R}$ to $2 \mathrm{R}$ keeping I unchanged
4 $\mathrm{R}$ to $2 \mathrm{R}$ and I to $2 \mathrm{I}$ keeping $\mathrm{N}$ unchanged
5 1 to $2 \mathrm{I}$ and keeping $\mathrm{N}$ and $\mathrm{R}$ unchanged
Moving Charges & Magnetism

153219 An electron is moving with a velocity $2 \times 10^{6}$ $\mathrm{m} / \mathrm{s}$ along positive $\mathrm{x}$-direction in the uniform electric field of $8 \times 10^{7} \mathrm{~V} / \mathrm{m}$ applied along positive y-direction. The magnitude and direction of a uniform magnetic field (in tesla) that will cause the electrons to move undeviated along its original path is

1 40 in - ve z-direction
2 40 in + ve z-direction
3 4 in + ve $z$-direction
4 4 in - ve z-direction
5 8 in + ve z-direction
Moving Charges & Magnetism

153220 A rectangular conducting loop of length $4 \sqrt{2} \mathrm{~m}$ and breadth $4 \mathrm{~m}$ carrying a current of $5 \mathrm{~A}$ in the anti-clockwise direction is placed in the $x y$ plane. The magnitude of the magnetic induction field vector $B$ at the intersection of the diagonal is $\quad\left(\right.$ use $\mu_{0}=4 \times 10^{-7} \mathrm{NA}^{-2}$ )

1 $1.2 \times 10^{-6} \mathrm{~T}$
2 $1.2 \times 10^{-5} \mathrm{~T}$
3 $2.4 \times 10^{-6} \mathrm{~T}$
4 $2.4 \times 10^{-5} \mathrm{~T}$
5 $1.2 \times 10^{-7} \mathrm{~T}$
Moving Charges & Magnetism

153221 A long straight wire carrying electric current $i$ is bent at its mid-point to form an angle of $45^{\circ}$ as shown in the figure. Magnetic field at a point $P$ at a distance $d$ from the point $Q$ of bending is

1 $\frac{\mu_{0} \mathrm{i}}{4 \pi \mathrm{d}}[\sqrt{2}-1]$
2 $\frac{\mu_{0} \mathrm{i}}{2 \pi \mathrm{d}}[\sqrt{2}-1]$
3 $\frac{\mu_{0} \mathrm{i}}{4 \pi \mathrm{d}}$
4 $\frac{\mu_{0} \mathrm{i}}{2 \pi \mathrm{d}}$