## MCQ (Single Correct Answer)

A long straight wire of length $$2 \mathrm{~m}$$ and mass $$250 \mathrm{~g}$$ is suspended horizontally in a uniform horizontal magnetic field of $$0....

A uniform electric field and a uniform magnetic field are acting along the same direction in a certain region. If an electron is projected in the regi...

A wire carrying a current $$I$$ along the positive $$\mathrm{x}$$-axis has length $$L$$. It is kept in a magnetic field $$\overrightarrow{\mathrm{B}}=...

A very long conducting wire is bent in a semi-circular shape from $$A$$ to $$B$$ as shown in figure. The magnetic field at point $$P$$ for steady curr...

The shape of the magnetic field lines due to an infinite long, straight current carrying conductor is

Two very long, straight, parallel conductors A and B carry current of 5 A and 10 A respectively and are at a distance of 10 cm from each other. The di...

The magnetic field on the axis of a circular loop of radius 100 cm carrying current $$I = \sqrt 2 \,A$$, at point 1 m away from the centre of the loop...

A long solenoid of radius 1 mm has 100 turns per mm. If 1 A current flows in the solenoid, the magnetic field strength at the centre of the solenoid i...

Given below are two statements:
Statement I : Biot-Savart's law gives us the expression for the magnetic field strength of an infinitesimal current el...

A square loop of side 1 m and resistance 1 $$\Omega$$ is placed in a magnetic field of 0.5 T. If the plane of loop is perpendicular to the direction o...

From Ampere's circuital law for a long straight wire of circular cross-section carrying a steady current, the variation of magnetic field in the insid...

An infinitely long straight conductor carries a current of 5A as shown. An electron is moving with a speed of 105 m/s parallel to the conductor. The p...

A long solenoid of 50 cm length having 100 turns carries a current of 2.5 A. The magnetic field at the centre of the solenoid is :$$\left( {{\mu _0} =...

A cylinderical conductor of radius R is carrying a constant current. The plot of the magnitude of the magnetic field. B with the distane d from the ce...

Ionized hydrogen atoms and $$\alpha $$-particles with same momenta enters perpendicular to a constant magnetic field, B. The ratio of their radii of t...

A metallic rod of mass per unit length
0.5 kg m–1 is lying horizontally on a smooth
inclined plane which makes an angle of 30° with
the horizontal. Th...

Current sensitivity of a moving coil
galvanometer is 5 div/mA and its voltage
sensitivity (angular deflection per unit voltage
applied) is 20 div/V. T...

An arrangement of three parallel straight wires placed perpendicular to plane of paper carrying same current $$'I'$$ along the same direction as shown...

A long wire carrying a steady current is bent into a circular loop of one turn. The magnetic field at the centre of the loop is B. It is then bent int...

An electron is moving in a circular path under the influence of a transverse magnetic field of 3.57 $$ \times $$ 10-2 T. If the value of e/m is 1.76 $...

A long straight wire of radius $$a$$ carries a steady current $$I$$. The current is uniformly distributed over its cross-section. The ratio of the mag...

A square loop ABCD carrying a current $$i$$, is placed near and coplanar with a long straight conductor XY carrying a current $$I$$, the net force on ...

A proton and an alpha particle both enter a region of uniform magnetic field B, moving at right angles to the field B. If the radius of circular orbit...

An electron moving in a circular orbit of radius r makes n rotations per second. The magnetic field produced at the centre has magnitude

A conducting square frame of side 'a' and a long straight wire carrying current $$I$$ are located in the same plane as shown in the figure. The frame ...

A wire carrying current $$I$$ has the shape shown in adjoining figure.
Linear parts of the wire are very long and parallel to X-axis while semicircu...

Two identical long conducting wires $$AOB$$ and $$COD$$ are placed at right angle to each other, with one above other such that $$O$$ is their common ...

In an ammeter 0.2% of main current passes through the galvanometer. If resistance of galvanometer is G, the resistance of ammeter will be

A long straight wire carries a certain current and produces a magnetic field 2 $$ \times $$ 10$$-$$4 Wb m$$-$$2 at a perpendicular distance of 5 cm fr...

A circular coil ABCD carrying a current 'i' is placed in a uniform magnetic field. If the magnetic force on the segment AB is $$\overrightarrow F $$, ...

When a proton is released from rest in a room, it starts with an initial acceleration $$a$$0 towards west. When it is projected towards north with a s...

A proton carrying 1 MeV kinetic energy is moving in a circular path of radius R in uniform magnetic field. What should be the energy of an $$\alpha $$...

A milli voltmeter of 25 milli volt range is to be converted into an ammeter of 25 ampare range. The value (in ohm) of neccessary shunt will be

Two similar coils of radius R are lying concentrically with their planes at right angles to each other. The currents flowing in them are $$I$$ and 2$$...

An alternating electric field, of frequency $$v$$, is applied across the does (radius = R) of a cyclotron that is being used to accelerate protons (ma...

A galvanometer of resistance, G, is shunted by a resistance S ohm. To keep the main current in the circuit unchanged, the resistance to be put in seri...

Charge q is uniformly spread on a thin ring of radius R. The ring rotates about its axis with a uniform frequency $$f$$ Hz. The magnitude of magnetic ...

A square loop, carrying a teady current $$I$$, is placed in a horizontal plane near a long straight conductor carrying a steady current $$I$$1 at a di...

A uniform electric field and a uniform magnetic field are acting along the same direction in a certain region. If an electron is projected in the regi...

A current carrying closed loop in the form of a right angle isosceles triangle ABC is placed in uniform magnetic field acting along AB. If the magneti...

A current loop consists of two identical semicircular parts each of radius R, one lying in the x-y plane and the other in x-z plane. If the current in...

A particle having a mass of 10$$-$$2 kg carries a charge of 5 $$ \times $$ 10$$-$$8 C. The particle is given an initial horizontal velocity of 105 m s...

A closely wound solenoid of 2000 turns and area of cross-section 1.5 $$ \times $$ 10$$-$$4 m2 carries a current of 2.0 A. It is suspended through its ...

Charge q is uniformly spread on a thin ring of radius R. The ring rotates about its axis with a uniform frequency $$f$$ Hz. The magnitude of magnetic ...

A galvanometer has a coil of resistance 100 ohm and gives a full scale deflection for 30 mA current. If it is to work as a voltmeter of 30 volt range,...

A square current carrying loop is suspended in a uniform magnetic field acting in the plane of the loop. If the force on one arm of the loop is the ne...

A galvanometer has a coil of resistance 100 ohm and gives a full scale deflection for 30 mA current. If it is to work as a voltmeter of 30 volt range,...

A galvanometer havings a coil resistance of 60 $$\Omega $$ shows full scale deflection when a current of 1.0 amp passes through it. It can be converte...

The magnetic force acting on a charged particle of charge $$-$$2 $$\mu $$C in a magnetic frield of 2 T acting in y direction, when the particle veloci...

Under the influence of a uniform magnetic field, a charged particle moves with constant speed v in a circle of radius R. The time period of rotation o...

A particle of mass m, charge Q and kinetic energy T enters a transverse uniform magnetic field of induction $$\overrightarrow B $$. After 3 seconds th...

A closed loop PQRS carrying a current is placed in a uniform magnetic field. If the magnetic forces on segments PS, SR and RQ are F1, F2 and F3 respec...

A galvanometer of resistance 50 $$\Omega $$ is connected to a battery of 3 V along with a resistance of 2950 $$\Omega $$ in series. A full scale defle...

Under the influence of a uniform magnetic field, a charged particle moves with constant speed v in a circle of radius R. The time period of rotation o...

The resistance of an ammeter is 13 $$\Omega $$ and its scale is graduated for a current upto 100 amps. After an additional shunt has been connected to...

When a charged particle moving with velocity $$\overrightarrow v $$ is subjected to a magnetic field of induction $$\overrightarrow B $$, the force on...

Two circular coils 1 and 2 are made from the same wire but the radius of the 1st coil is twice that of the 2nd coil. What is the ratio of potential di...

An electron moves in a circular orbit with a uniform speed v. It producess a magnetic field B at the centre of the circle. The radius of the circle is...

A very long straight wire carries a current $$I$$. At the instant when a charge +Q at point P has velocity $$\overrightarrow v $$, as shown, the force...

A galvanometer of 50 ohm resistance has 25 divisions. A current of 4 $$ \times $$ 10$$-$$4 ampere gives a deflection of one division. To convert this ...

To convert a galvanometer into a voltmeter one should connect a

A long solenoid carrying a current producess a magnetic field B along its axis. If the current is doubled and the number of turns per cm is halved, th...

A charged particle moves through a magnetic field in a firection perpendicular to it. Then the

To convert a galvanometer into a voltmeter one should connect a

A charge q moves in a region where electric field and magnetic field both exist, then force on it is

The magnetic field of given length of wire for single turn coil at its centre is B then its value for two turns coil for the same wire is

If number of turns, area and current through a coil is given by n, A and $$i$$ respectively then its magnetic moment will be

An electron having mass m and kinetic energy E anter in uniform magnetic field B perpendiculaly, then its frequency will be

The magnetic field at centre, P will be
...