04. Force and Torque on Current Carrying Conductor
Moving Charges & Magnetism

153777 A semi-circular loop of radius $30 \mathrm{~cm}$ wire carries current $6 \mathrm{~A}$. An uniform magnetic field $0.5 \mathrm{~T}$ is present perpendicular to the plane of the loop. What is the magnitude of force exerted on the wire?

1 $0.9 \mathrm{~N}$
2 $1.8 \mathrm{~N}$
3 $0.8 \mathrm{~N}$
4 $1.4 \mathrm{~N}$
Moving Charges & Magnetism

153778 The magnitude of the force vector acting on a unit length of a thin wire carrying a current $I=$ $8 \mathrm{~A}$ at a point $O$, if the wire is bent as shown in the figure with a radius, $R=10 \pi \mathrm{cm}$ is

1 $64 \mu \mathrm{N} / \mathrm{m}$
2 $32 \mu \mathrm{N} / \mathrm{m}$
3 $20 \mu \mathrm{N} / \mathrm{m}$
4 $100 \mu \mathrm{N} / \mathrm{m}$
Moving Charges & Magnetism

153779 A square loop, carrying a steady current $I$, is placed in a horizontal plane near a long straight conductor carrying a steady current $I_{1}$ at a distance $d$ from the conductor as shown in figure. The loop will experience

1 a net repulsive force away from the conductor
2 a net torque acting upward perpendicular to the horizontal plane
3 a net torque acting downward normal to the horizontal plane
4 a net attractive force towards the conductor
Moving Charges & Magnetism

153780 Two parallel very long straight wires carrying current of $5 \mathrm{~A}$ each are kept at a separation of 1 $m$. If the currents are in the same direction, the force per unit length between them is $\mathrm{N} / \mathbf{m}$. $\left(\mu_{0}=4 \pi \times 10^{-7} \mathrm{SI}\right)$.

1 $5 \times 10^{-5}$, attraction
2 $5 \times 10^{-6}$, attraction
3 $5 \times 10^{-5}$, repulsive
4 $5 \times 10^{-6}$, repulsive
Moving Charges & Magnetism

153781 The work done in placing a charge of $8 \times 10^{-18} \mathrm{C}$ on a condenser of capacity $100 \mu \mathrm{F}$ is

1 $16 \times 10^{-32} \mathrm{~J}$
2 $3.1 \times 10^{-26} \mathrm{~J}$
3 $4 \times 10^{-10} \mathrm{~J}$
4 $32 \times 10^{-32} \mathrm{~J}$
Moving Charges & Magnetism

153777 A semi-circular loop of radius $30 \mathrm{~cm}$ wire carries current $6 \mathrm{~A}$. An uniform magnetic field $0.5 \mathrm{~T}$ is present perpendicular to the plane of the loop. What is the magnitude of force exerted on the wire?

1 $0.9 \mathrm{~N}$
2 $1.8 \mathrm{~N}$
3 $0.8 \mathrm{~N}$
4 $1.4 \mathrm{~N}$
Moving Charges & Magnetism

153778 The magnitude of the force vector acting on a unit length of a thin wire carrying a current $I=$ $8 \mathrm{~A}$ at a point $O$, if the wire is bent as shown in the figure with a radius, $R=10 \pi \mathrm{cm}$ is

1 $64 \mu \mathrm{N} / \mathrm{m}$
2 $32 \mu \mathrm{N} / \mathrm{m}$
3 $20 \mu \mathrm{N} / \mathrm{m}$
4 $100 \mu \mathrm{N} / \mathrm{m}$
Moving Charges & Magnetism

153779 A square loop, carrying a steady current $I$, is placed in a horizontal plane near a long straight conductor carrying a steady current $I_{1}$ at a distance $d$ from the conductor as shown in figure. The loop will experience

1 a net repulsive force away from the conductor
2 a net torque acting upward perpendicular to the horizontal plane
3 a net torque acting downward normal to the horizontal plane
4 a net attractive force towards the conductor
Moving Charges & Magnetism

153780 Two parallel very long straight wires carrying current of $5 \mathrm{~A}$ each are kept at a separation of 1 $m$. If the currents are in the same direction, the force per unit length between them is $\mathrm{N} / \mathbf{m}$. $\left(\mu_{0}=4 \pi \times 10^{-7} \mathrm{SI}\right)$.

1 $5 \times 10^{-5}$, attraction
2 $5 \times 10^{-6}$, attraction
3 $5 \times 10^{-5}$, repulsive
4 $5 \times 10^{-6}$, repulsive
Moving Charges & Magnetism

153781 The work done in placing a charge of $8 \times 10^{-18} \mathrm{C}$ on a condenser of capacity $100 \mu \mathrm{F}$ is

1 $16 \times 10^{-32} \mathrm{~J}$
2 $3.1 \times 10^{-26} \mathrm{~J}$
3 $4 \times 10^{-10} \mathrm{~J}$
4 $32 \times 10^{-32} \mathrm{~J}$
Moving Charges & Magnetism

153777 A semi-circular loop of radius $30 \mathrm{~cm}$ wire carries current $6 \mathrm{~A}$. An uniform magnetic field $0.5 \mathrm{~T}$ is present perpendicular to the plane of the loop. What is the magnitude of force exerted on the wire?

1 $0.9 \mathrm{~N}$
2 $1.8 \mathrm{~N}$
3 $0.8 \mathrm{~N}$
4 $1.4 \mathrm{~N}$
Moving Charges & Magnetism

153778 The magnitude of the force vector acting on a unit length of a thin wire carrying a current $I=$ $8 \mathrm{~A}$ at a point $O$, if the wire is bent as shown in the figure with a radius, $R=10 \pi \mathrm{cm}$ is

1 $64 \mu \mathrm{N} / \mathrm{m}$
2 $32 \mu \mathrm{N} / \mathrm{m}$
3 $20 \mu \mathrm{N} / \mathrm{m}$
4 $100 \mu \mathrm{N} / \mathrm{m}$
Moving Charges & Magnetism

153779 A square loop, carrying a steady current $I$, is placed in a horizontal plane near a long straight conductor carrying a steady current $I_{1}$ at a distance $d$ from the conductor as shown in figure. The loop will experience

1 a net repulsive force away from the conductor
2 a net torque acting upward perpendicular to the horizontal plane
3 a net torque acting downward normal to the horizontal plane
4 a net attractive force towards the conductor
Moving Charges & Magnetism

153780 Two parallel very long straight wires carrying current of $5 \mathrm{~A}$ each are kept at a separation of 1 $m$. If the currents are in the same direction, the force per unit length between them is $\mathrm{N} / \mathbf{m}$. $\left(\mu_{0}=4 \pi \times 10^{-7} \mathrm{SI}\right)$.

1 $5 \times 10^{-5}$, attraction
2 $5 \times 10^{-6}$, attraction
3 $5 \times 10^{-5}$, repulsive
4 $5 \times 10^{-6}$, repulsive
Moving Charges & Magnetism

153781 The work done in placing a charge of $8 \times 10^{-18} \mathrm{C}$ on a condenser of capacity $100 \mu \mathrm{F}$ is

1 $16 \times 10^{-32} \mathrm{~J}$
2 $3.1 \times 10^{-26} \mathrm{~J}$
3 $4 \times 10^{-10} \mathrm{~J}$
4 $32 \times 10^{-32} \mathrm{~J}$
Moving Charges & Magnetism

153777 A semi-circular loop of radius $30 \mathrm{~cm}$ wire carries current $6 \mathrm{~A}$. An uniform magnetic field $0.5 \mathrm{~T}$ is present perpendicular to the plane of the loop. What is the magnitude of force exerted on the wire?

1 $0.9 \mathrm{~N}$
2 $1.8 \mathrm{~N}$
3 $0.8 \mathrm{~N}$
4 $1.4 \mathrm{~N}$
Moving Charges & Magnetism

153778 The magnitude of the force vector acting on a unit length of a thin wire carrying a current $I=$ $8 \mathrm{~A}$ at a point $O$, if the wire is bent as shown in the figure with a radius, $R=10 \pi \mathrm{cm}$ is

1 $64 \mu \mathrm{N} / \mathrm{m}$
2 $32 \mu \mathrm{N} / \mathrm{m}$
3 $20 \mu \mathrm{N} / \mathrm{m}$
4 $100 \mu \mathrm{N} / \mathrm{m}$
Moving Charges & Magnetism

153779 A square loop, carrying a steady current $I$, is placed in a horizontal plane near a long straight conductor carrying a steady current $I_{1}$ at a distance $d$ from the conductor as shown in figure. The loop will experience

1 a net repulsive force away from the conductor
2 a net torque acting upward perpendicular to the horizontal plane
3 a net torque acting downward normal to the horizontal plane
4 a net attractive force towards the conductor
Moving Charges & Magnetism

153780 Two parallel very long straight wires carrying current of $5 \mathrm{~A}$ each are kept at a separation of 1 $m$. If the currents are in the same direction, the force per unit length between them is $\mathrm{N} / \mathbf{m}$. $\left(\mu_{0}=4 \pi \times 10^{-7} \mathrm{SI}\right)$.

1 $5 \times 10^{-5}$, attraction
2 $5 \times 10^{-6}$, attraction
3 $5 \times 10^{-5}$, repulsive
4 $5 \times 10^{-6}$, repulsive
Moving Charges & Magnetism

153781 The work done in placing a charge of $8 \times 10^{-18} \mathrm{C}$ on a condenser of capacity $100 \mu \mathrm{F}$ is

1 $16 \times 10^{-32} \mathrm{~J}$
2 $3.1 \times 10^{-26} \mathrm{~J}$
3 $4 \times 10^{-10} \mathrm{~J}$
4 $32 \times 10^{-32} \mathrm{~J}$
Moving Charges & Magnetism

153777 A semi-circular loop of radius $30 \mathrm{~cm}$ wire carries current $6 \mathrm{~A}$. An uniform magnetic field $0.5 \mathrm{~T}$ is present perpendicular to the plane of the loop. What is the magnitude of force exerted on the wire?

1 $0.9 \mathrm{~N}$
2 $1.8 \mathrm{~N}$
3 $0.8 \mathrm{~N}$
4 $1.4 \mathrm{~N}$
Moving Charges & Magnetism

153778 The magnitude of the force vector acting on a unit length of a thin wire carrying a current $I=$ $8 \mathrm{~A}$ at a point $O$, if the wire is bent as shown in the figure with a radius, $R=10 \pi \mathrm{cm}$ is

1 $64 \mu \mathrm{N} / \mathrm{m}$
2 $32 \mu \mathrm{N} / \mathrm{m}$
3 $20 \mu \mathrm{N} / \mathrm{m}$
4 $100 \mu \mathrm{N} / \mathrm{m}$
Moving Charges & Magnetism

153779 A square loop, carrying a steady current $I$, is placed in a horizontal plane near a long straight conductor carrying a steady current $I_{1}$ at a distance $d$ from the conductor as shown in figure. The loop will experience

1 a net repulsive force away from the conductor
2 a net torque acting upward perpendicular to the horizontal plane
3 a net torque acting downward normal to the horizontal plane
4 a net attractive force towards the conductor
Moving Charges & Magnetism

153780 Two parallel very long straight wires carrying current of $5 \mathrm{~A}$ each are kept at a separation of 1 $m$. If the currents are in the same direction, the force per unit length between them is $\mathrm{N} / \mathbf{m}$. $\left(\mu_{0}=4 \pi \times 10^{-7} \mathrm{SI}\right)$.

1 $5 \times 10^{-5}$, attraction
2 $5 \times 10^{-6}$, attraction
3 $5 \times 10^{-5}$, repulsive
4 $5 \times 10^{-6}$, repulsive
Moving Charges & Magnetism

153781 The work done in placing a charge of $8 \times 10^{-18} \mathrm{C}$ on a condenser of capacity $100 \mu \mathrm{F}$ is

1 $16 \times 10^{-32} \mathrm{~J}$
2 $3.1 \times 10^{-26} \mathrm{~J}$
3 $4 \times 10^{-10} \mathrm{~J}$
4 $32 \times 10^{-32} \mathrm{~J}$