12th Class PHYSICS MCQs CHAPTER NO.3 ELECTROMAGNETISM Test No.1

The unit of magnetic flux is

Magnetic force performs

If the current passing through a wire in a magnetic field is halved the magnetic force would become

Lorentz force is given by

CRO is used for displaying the wave form of a given

In CRO, beam of electrons is focused by

The e/m of an electron moving in a circular path in a magnetic field is given by

In CRO the x-plates deflect the beam of electrons _________ on screen

One tesla is equal to

Ampere's law can be used to calculate the_______field

In CRO when cathode is .heated by a filament, it emits

An ideal ammeter has ________resistance

Magnetic flux will be minimum when

A 5 meter wire carrying a current of 2 A is at right angles to the uniform magnetic field of 0.5 weber/(m² The force on the wire is

A magnetic field is always set up due to

Total number of lines of magnetic induction passing through any surface placed perpendicular to the field is called:

A 0.50 T field over an area of 2 (m²) which lies at an angle of 30^° to the field, the magnetic flux is

When an electron enters in a magnetic field, right angle to its motion. then the magnitude of velocity will be

Two parallel straight wires carrying currents in opposite direction

The force experienced by a single charge carrier moving with velocity V^→ in a magnetic field of strength B^→ is given by

The grid in CRO

If current is passing through a wire, lines of force near it are

CRO when beam of electrons falls on screen; it makes a visible spot because the screen is

A current carrying wire is surround by

Which of the following particle moving in the magnetic field cannot be deflected

Magnetic field along the axis of a solenoid with N turns carrying a current I is given by

In western type galvanometer, the jeweled bearings are used produced

The magnetic force is simply a

Magnetic flux per unit area perpendicular to magnetic field is called

In galvanometer the coil is situated in the magnetic field such that the plane of the coil is always

Magnetic flux density due to current carrying conductor can be determined by

A long tightly wound cylindrical coil of wire is called

The galvanometer in which the coil comes to rest quickly after the current passed through it, is called

The magnetic effect near the current carrying conductor was discovered by

An ammeter only can be used in________ in a circuit

The magnetic field at a point due to a current carrying conductor is directly proportional to

The magnetic force experienced by a charge particle is zero, when charge particle is projected at

The magnitude of the deflecting torque on a current carrying coil in

The relation between current I and the angle of deflection in a moving coil galvanometer is:

In e/m experiment, the path of the electron can be made visible by filling glass tube with

Magnetic field inside a long solenoid is

A galvanometer is converted into an ammeter by connecting a suitable

Torque necessary to produce unit twist is called

In CRO the grid is at _______potential with respect to cathode

A current carrying conductor experiences maximum magnetic force in a uniform magnetic field when it-is placed

In SI units, the value of permeability of free space (μ) is

A charge projected in the direction of magnetic field experiences

When a charged particle moves through a magnetic field, the effect of the field, changes the particle's

The working of galvanometer depends upon torque on a current carrying coil in

The current passing through a coil of galvanometer is given by

SI unit of magnetic flux is

The waveform produced by sweep or time base generator in CRO is

The e/m of an electron can be expressed as

The electron, gun in CRO consists of

Magnetic flux will be maximum when

The galvanometer can be made sensitive if the value of the factor BAN/C is

Charge to mass ratio of neutron is__________ that of electron

When charged particle enters perpendicular in magnetic field, it moves in

When the coil of the galvanometer is in equilibrium; then the deflecting couple is

A high speed graph plotting device is

The direction of lines of force depends upon the direction of

Minimum current required to produce a deflection of one mm on a scale at a distance of 1 meter is

Charge to mass ratio (e/m) of a proton is_________ that of electron

Which of the, following is most suitable for the core of an electromagnet?

Ammeter is a

When an electron enters in a perpendicular magnetic field of its motion. then direction of its motion

The force Experienced by a charge particle is maximum if it moves

The beam of electrons in CRO is deflected when they pass through uniform

The SI unit of magnetic induction is

Sensitivity of Galvanometer can he increased by increasing

The magnetic force experienced by a chai.ge particle is maximum, when charge particle is projected at

The Working of a galvanometer depends upon

When current passes through a solenoid coil, it behaves like a

The working of all electrical instruments depends upon

One tesla is equal to

The SI units of magnetic permeability is

In galvanometer, the restoring couple of the suspension wire is proportional to the angle of deflection as long as the wire obeys

Two parallel straight wires carrying currents in same direction

Which one of the following field is suitable choice for circular trajector of a charged partical

Cathode ray oscilloscope works by deflecting beam of

The mathematical expression Σ [(B^→). (l^→)] = (µ₀I) is known as

The magnetic field outside the solenoid due to current is

In a galvanometer, the enameled copper wire is wound on

A device used for the detection of current is called

The magnetic field in a certain region is given by (B^→) = (40i^{^})-(18j^{^}). How much flux passes a 5.0 cm² area loop in this region if the loop lies hate in the xy-plane

The sensitivity of a moving coil galvanometer can be, increased by

In a straight current carrying conductor, the direction of magnetic field can be found by

In a moving coil galvanometer, the deflecting. Torque depends upon

The current passing through coil of the galvanometer is

In galvanometer the rectangular coil is made up of

If an electron enters the perpendicular magnetic field with a velocity v^→ it will experience a force which is given by F=

When a current carrying conductor is placed in a uniform magnetic field, it experience a force which is given by

Sensitivity of galvanometer is given by

The brightness of the spot On CRO screen is controlled by

When charged particle is projected perpendicular to a uniform magnetic field its trajectors is

In velocity selector a charged particle will go undeflecting if V is equal to