Recent questions tagged ch4

A metallic wire is folded to form a square loop of side $a$. It carries a current $i$ and is kept $ \perp$ to a uniform magnetic field. If the shape of the loop is changed from a square to a circle without changing its length or current, the amount of work done is

asked Feb 23, 2014 by thanvigandhi_1

1 answer

A particle having charge $q$ enters a region of uniform magnetic field $B$ directed inwards and is deflected as shown to a distance $d$ above the original line of flight as shown. What is the (magnitude of) momentum of the particle?

asked Feb 23, 2014 by thanvigandhi_1

1 answer

An electron moving with a speed $u$ along the $+ve\: x$ - axis and at $y = 0$ enters a region of uniform magnetic field $\overrightarrow B = -B_0 \hat k $ after sometime with speed $v$ at co-ordinate $ y$, then which exists to the right of the $ y$ - axis. The electron exits from the region

asked Feb 23, 2014 by thanvigandhi_1

1 answer

Velocity and acceleration vector of a charged particle moving in a magnetic field at some instant are $ \overrightarrow V = 3\hat i + 4\hat j\: and\: \overrightarrow B= 2\hat i + x \hat j$. Select the incorrect alternative

asked Feb 23, 2014 by thanvigandhi_1

1 answer

Two identical coils are placed coaxially. They carry equal currents in the same direction. Then

asked Feb 23, 2014 by thanvigandhi_1

1 answer

A rigid circular loop of radius $ r$ lies in the $x-y$ plane on a flat table and a current $i$ flows through it. At this place, the earth’s magnetic field is $B_x\hat i + B_z \hat k$ . The value of $i$ so that one end of the loop lifts up from the table is

asked Feb 23, 2014 by thanvigandhi_1

1 answer

A conducting rod of mass $m$ and length $L$ is moving down a smooth incline plane on inclination $ \theta$ with constant velocity $ v$. A current $i$ is flowing in the conductor in a direction perpendicular to the paper inwards. A vertically upward magnetic field $ \overrightarrow B$ exists in space. Its magnitude is

asked Feb 23, 2014 by thanvigandhi_1

1 answer

The dimensions of $ \large\frac{B^2C^2R^2}{2\mu_0}$ where $B$ is magnetic field,$ R$ is resistance and $ C$ is capacitance are

asked Feb 23, 2014 by thanvigandhi_1

1 answer

Magnetic field at the centre of a circular loop of area $A$ is $B$. Then magnetic moment of the loop is

asked Feb 23, 2014 by thanvigandhi_1

1 answer

A proton, a deuteron and an $ \alpha$ - particle having the same kinetic energy are moving in circular trajectories in a constant magnetic field. If $r_p, r_d$ and $r_{\alpha}$ denote respectively the radii of the trajectories of these particles, then

asked Feb 23, 2014 by thanvigandhi_1

1 answer

A battery is connected between two points $A$ and $B$ on the circumference of a uniform conducting ring of radius $r$ and resistance $R$. One of the arcs $AB$ of the ring subtends an angle $ \theta$ at the centre. The intensity of the magnetic field at the centre due to a constant current in the ring is

asked Feb 23, 2014 by thanvigandhi_1

1 answer

A circular loop of radius $R$, carrying a current $i$ lies in the $x-y$ plane with its centre at the origin. The total magnetic flux through the $x-y$ plane is

asked Feb 22, 2014 by thanvigandhi_1

1 answer

The magnetic field at the centre of an equilateral triangular loop of side $2L$ carrying a current $i$ is

asked Feb 22, 2014 by thanvigandhi_1

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Same current is flowing in three infinitely long wires along positive $x, y$ and $z$ directions. The magnetic field at the point $(0, 0, -a)$ would be

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A wire of length $\ell$ is bent to form a circular coil of some turns. A current $i$ flows through the coil and is placed in a uniform magnetic field $B$. The maximum torque on the coil can be

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A conducting rod of mass $m$ and length $\ell$ is placed over a smooth table. A uniform magnetic field is acting perpendicular to the rod. Charge $q$ is suddenly passed through the rod and it acquires a velocity $v$ on the surface, then $q$ is equal to

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A charged particle is projected with velocity $ \upsilon_0$ along the positive $x$ - axis. The magnetic field $B$ is directed along negative $z$ - axis for the region $0<x<L$. The particle emerges out at $x = L$ at an angle of $60^{\circ}$ with the direction of projection. Find the velocity with which the same particle is projected at $x=0$ along the $+ve\: x$ - axis so that when it emerges out at $x = L$, the angle made by it is $30^{\circ}$ direction of projection with the

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A charge particle moves in a circular path in possible electric and magnetic fields. Which of the following scenarios is possible?

asked Feb 22, 2014 by thanvigandhi_1

1 answer

In a coaxial straight cable, the central conductor and the outer conductor carry equal currents in opposite directions. The magnetic field is zero

asked Feb 22, 2014 by thanvigandhi_1

1 answer

Two parallel wires carry currents $20A$ and $40A$ in the opposite directions. Another wire carrying a current $30A$ parallel to $40A$ is placed mid-way between the two wires. The force on it will be

asked Feb 22, 2014 by thanvigandhi_1

1 answer

An electric current $\imath$ enters and leaves a uniform circular wire of radius $ \Re$ through diametrically opposite points. A charged particle q moving along the axis of the circular wire passes through the centre at speed $v$. The magnetic force acting on the particle when it passes through the centre is

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A ring of mass m, radius R having charge q uniformly distributed over it and free to rotate about its own axis is placed in a region having a magnetic field B parallel to its axis. If the magnetic field is suddenly switched off, the angular velocity acquired by the ring is

asked Feb 22, 2014 by thanvigandhi_1

1 answer

Circular arc of a wire of radius R makes an angle of 3π/2 radians at the centre. If a current i flows through it, the magnetic field intensity at the centre of the circle will be

asked Feb 22, 2014 by thanvigandhi_1

1 answer

Two parallel connecting wires placed at a distance d apart carry equal currents in the same direction then the intensity of the magnetic field at a point between them will be

asked Feb 22, 2014 by thanvigandhi_1

1 answer

A uniform magnetic field exists in a region which forms an equilateral triangle of side $a$. The field is perpendicular to the plane of the triangle. A charge $q$ enters the triangle with speed $v$ along the $ \perp$ bisector of one of the sides and comes out along the $\perp$ bisector of the other side. Intensity of the magnetic field is

asked Feb 22, 2014 by thanvigandhi_1

1 answer

Consider the following statements \[\] Statement 1: If a charged particle is released in a region of uniform electric and magnetic fields parallel to each other, it will move in a straight line \[\] Statement 2: The magnetic field exerts no force on the particle but electric field does

asked Feb 22, 2014 by thanvigandhi_1

1 answer

Consider the following statements \[\] Statement 1: A long straight conductor carrying a current lies along the axis of a current carrying ring. The conductor will not exert any force on the ring \[\] Statement 2: The magnetic field due to a straight conductor coincides with the ring

asked Feb 22, 2014 by thanvigandhi_1

1 answer