LMS

V=20 sin200πt, then frequency of this A.C voltage will be:

The root mean square (rms) values of current and voltage are

Vrms is ___________percent of peak value

The magnetic field in a certain region is 5Wbm^-2. How much flux passes through an area of 20m², if a loop is placed at right angle to the field

The phase of A.C at the positive peak from origin is:

The graph shows how an alternating current I of peak value I0 varies with time .Which expression gives the alternating current I?

During one cycle, the direction of flow of alternating current

The unit of magnetic flux is:

A coil is placed near a magnet. Emf will be induce in it when

Unit of induced emf is

An electron of mass m is accelerated through a potential difference of V and then it enters a magnetic field of induction B normal to the lines. Then the radius of the circular path is

Proton and – particle enter with same velocity at 180o with a uniform magnetic field. Ratio of radius of their paths will be:

Work done by magnetic force is

A particle of charge q is stationary at a place where the magnetic field is B along the x-axis. The force on the charge due to B is:

Which of the following quantities is not affected by a magnetic field?

A proton is moving with a velocity of 3 x 10⁷ m / s in the direction of a uniform magnetic field of 0.5 Tesla. The force acting on proton is.

A conductor of length 1 m carrying a current of 1 A is placed parallel to a magnetic field of 1 T. The magnetic force acting on the conductor is

A steady current is flowing through a cylindrical conductor

A uniform electric field and a uniform magnetic field exist in a region in the same direction .An electron is projected with velocity pointed in the same direction. The electron will

Two charges are projected in a magnetic field. Their paths after entering field is shown in figure. What type of these charges are?

A charged particle moving in a magnetic field experiences a force given by:

The north pole of a long horizontal bar magnet is being brought close to a vertical conducting plane along the perpendicular direction. The direction of induced current in the conducting plane will be

In step up transformer, voltage in the secondary increases and power in secondary

A coil having 500 square loops, each of side 10 cm, is placed normal to a magnetic field which increases at the rate of 1.0T/s. The induced emf in volts is

Eddy Currents are

Transformer is based on the principle of

The diagram shows how the e.m.f. of a simple generator varies with time. What is the frequency and the maximum value of the e.m.f?

An electron is injected into a uniform magnetic field with components of velocity parallel to and normal to the field direction. The path of the electron is a

The e/m of neutron is

An electron of mass ‘m’ is accelerated through a potential difference of (V) and then it enters a magnetic field of induction (B) normal to the lines. Then the radius of the circular path is.

Which of the following does not affect the motion of a moving electron?

Two parallel wires carrying equal currents of 10 A attract each other with a force of 1 mN. If both currents are doubled, the force of attraction will be:

In case of a straight conductor, the magnetic lines of force are

Electric field of 1500 Vm^-1 and magnetic field “B” are perpendicular to each other. If an electron moving with speed 300 m/s passes straight through this region then the value of B in tesla is

Refer to the figure maximum deflection in the galvanometer occurs when

In step up transformer, voltage in the secondary increases and power in secondary

A magnetic field that is uniform can be found

The ability of a material to conduct magnetic flux through it.

In case of a straight conductor, the magnetic lines of force are

One Wbm^-2 is equal to

In a circular coil, the current is found to be flowing in anticlockwise direction. In which direction is the magnetic field produced at a point on the axis of the coil?

A metallic ring is attached with the wall of a room. When the north pole of a magnet is brought near to it, the induced current in the ring will be

Lenz's law gives

A transformer is employed to

The transformation ratio in the step-up transformer is

In a transformer 220 ac voltage is increased to 2200 volts. If the number of turns in the secondary are 2000, then the number of turns in the primary will be

A proton charge (+e coulomb C) enters in a magnetic field of strength B(Tesla) making an angle 30o with the direction of magnetic field with speed v. The magnetic force on the proton is

A long straight wire carries a current of 2A. Find the magnitude of magnetic field at a distance 0.5 m from the wire

A magnetic field is applied perpendicular to the plane of a flat coil of copper wire. The time variation of the magnetic flux density is given by Bo sin (2pt/T), as shown graphically in Fig.At which of the following values of t is the magnitude of the emf induced in the coil is maximum?