Magnetic effect of electric current was first discovered by

A conductor carrying a current ‘I’ has length ‘L’. When it is placed in a magnetic field, ‘B’ at 90 degrees , it experiences a force:

NTS 2016 DUHS & JSMU
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

Due to the magnetic force, a positively charged particle executes uniform circular motion within a uniform magnetic field ‘B’. If the charge is ‘q’ and radius of its path is r, which of the expressions gives the magnitude of the particle’s linear momentum:

NTS 2010
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

When a charged particle is projected perpendicular to a magnetic field:

NUMS 2016
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

Magnetic force on a moving charge depends upon:

NTS 2016 SMBBMC
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

What are dimensions of Magnetic Flux

If a stationary bar magnet is placed near a coil so that maximum lines of force passes through the coil, the galvanometer shows:

PMC 2020
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

If the current in the wire is directed into the page, and the wire is held perpendicular to the page, then the direction of magnetic circles will be:

_______ is a device which makes use of mutual induction for stepping up or down an alternating e.m.f.

NTS 2012
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

A particle of charge -0.04C is projected with speed 2 x 104 m/s into a uniform magnetic field ‘B’ of strength 0.5 T. If the particle’s velocity as it enters the field is perpendicular to ‘B’, what is the magnitude of the magnetic force on this particle:

NTS 2010
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

A magnetic needle is placed in a uniform magnetic field and is aligned with the field. The needle is now rotated by an angle of 60 degrees and work done is W. The torque on the magnetic needle at this position is

NUMS 2014
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

Two parallel straight conductors, in which current is flowing in the same direction, attract each other. The cause of it is:

PMC 2020
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

If a wire having current 10A has a 3T magnetic field, what will be the magnetic field at a point from the wire at double the distance?

NUMS 2016
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

When a transformer is connected to 120-volt ac, it supplies 3000 V to a device. The current through the secondary winding then is o.06 A and the current through the primary is 2 A. The number of turns in the primary winding is 400. The number of turns in the secondary winding is:

NTS 2016 DUHS & JSMU
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

Moving charge produce field

How fast an H+ ion should move in magnetic field 2.5×10-3 T such that magnetic force equal its weight?

NUMS 2016
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

If a certain region’s magnetic field is directed vertically up and a proton enters this field from the left side, it will go _________.

NUMS 2019 Reconduct
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

An A.C emf of E = 100 sin (100 π t) volt is concerned with a choke of negligible resistance. In order to produce current of amplitude 1 A, the inductance of the choke should be:

NUMS 2015
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

In a circuit, there is a current of 5 amp which is changed such that the current falls to zero in 0.1 sec. If an average e.m.f. of 200 volts is induced, the self-inductance of the circuit will be:

NTS 2012
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

What is the flux density at a point 3 cm from the long straight wire, when there is a current of 25 A in a wire: (u0= 4? x10-7)

NTS 2010
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

If a constant current is flowing through a coil, then the flux through that coil will become constant. In such types of arrangements, the electromotive force (emf) induced in the coil will be:

NTS 2018
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

Magnetic flux is maximum when angle between magnetic field and vector area is:

PMC 2020
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

F = I L B, What Is relation between I and L

The combination of ammeter, voltmeter, and ohmmeter into a compact single meter with one common galvanometer is called:

NTS 2015 SMBBMC
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

A current carrying conductor is lying perpendicular to magnetic field and experiencing some force. If the conductor rotates by 60 degrees counter clock wise, the force on it will

What is the device which is used to measure magnetic field

If length of solenoid gets doubled while keeping N (number of turns) constant, the resultant magnetic field will be?

In a certain circuit, a transistor has a collector current of 10mA and a base current of 40μA. What is the current gain of the transistor?

NTS 2015 DUHS and JSMU
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

There is a current of 25 A in a long straight wire. What is the flux density at a point 3 cm from the wire?

NTS 2016 SMBBMC
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

If current passing through a solenoid is increased, which of the following must increase:

Four particles independently move at the same speed in a direction perpendicular to the same magnetic field. Which particle is deflected the most?

NTS 2017
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

In a coil, when current changes from 10 A to 4 A in 1 s. An induced emf of 1.2 V is induced across the coil. The self – inductance of the coil is:

NUMS 2019 Cancelled
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

If the length of a current carrying solenoid is doubled keeping the number of turns same and the current is increased to 9 times, the value of magnetic field compared to the original magnetic field B will be:

The SI unit of magnetic flux is Weber which is equivalent to:

NUMS 2019 Reconduct
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

If electron passes through axis of solenoid the movement will be:

NUMS 2016
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

Weber x ampere per meter is equal to:

NUMS 2016
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

By changing the current through the same coil, an emf is induced in it, the process is known as:

NTS 2015 SMBBMC
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

The current measuring part of the Avometer consists of a number of low resistors connected …

NUMS 2016
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

If two inductors each of Inductance L are Introduced in a circuit in parallel, the equivalent Inductance will be:

Unit of Magnetic Flux is

Unit of magnetic flux density is

The direction of the magnetic line of force depends upon:

NUMS 2016
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

Transformer works on the principle of:

NTS 2016 SMBBMC
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

A 3-cm length of wire is moved at right angles across a uniform magnetic field with a speed of 2.0 m/s . If the flux density is 5.0 teslas, what is the magnitude of the induced e.m.f?

NUMS 2015
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

1 testa is equal to?

A circuit in which there is a current of 10 amperes is changed so that the current falls to zero in 0.5 seconds. If an average e.m.f. of 400 volts is induced, what is the self-inductance of the circuit?

NTS 2015 DUHS and JSMU
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

A coil of 600 turns is threaded by a flux of 8×10-5 webers if this flux is reduced to 3×10-5 webers in 0.015 seconds. The average induced e.m.f. is:

NTS 2011
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

An electron enters in a magnetic field at an angle less than 90 degrees with magnetic field. Which of the following path is followed by an electron?

NUMS 2014
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

EEG is related to:

The brightness spot on the screen in the CRO is controlled by:

Transformer is a device which steps up or steps down the input:

PMC 2020
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

Ammeter Is a galvanometer with:

A 20.0 cm wire carrying a current of 10.0 A is placed in a uniform magnetic field of 0.30 T. If the wire makes an angle of 40° with the direction of the magnetic field, find the magnitude of the force acting on the wire? ( sin 40° = 0.642)

NTS 2015 DUHS and JSMU
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

the value of permeability

A conductor of length L is moved across a magnetic field. Due to this activity, a potential difference appears across the ends of the conductor. This type of potential difference is termed as:

NTS 2018
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

Identify the instrument/s which is/are used for the measurement of resistance:

I. Wheatstone Bridge

II. Meter Bridge

III. Post office Box

IV. Ohmmeter

NTS 2015 DUHS and JSMU
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

In CRO, electrons are emitted from:

A proton is about 1840 times heavier than an electron. When it is accelerated by a potential difference of 1kV, its kinetic energy will be:

NUMS 2016
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

In transmission from grid station, power losses are minimized by:

PMC 2020
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

A bar magnet has a magnetic moment 200 Am2. The magnet is suspended in a magnetic field of 0.30 NA-1m-1. The torque required to rotate the magnet from its equilibrium position at an angle of 30˚ will be:

NUMS 2014
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

A circuit in which there is a current of 5 amp is changed so that the current falls to zero in 0.1s. If an average e.m.f of 200 volts is induced, what is the self-inductance of the circuit?

NTS 2014
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

Two point charges of +5 C and -12 C attract each other with a force of 1.48 N. charge of -5 C is added to each of these charges. Now the force will be:

NUMS 2015
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

Ammeter lies in

Which of the following is incorrect?

A torold is?  l• A circular ring shape of a coil. II- A solenoid bent In shape of a circle. a) I only b) II only

ECG records

An electron is moving along the axis of a solenoid carrying a current. Which of the following is a correct statement about the electromagnetic force acting on the electron?

NUMS 2015
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

What is true regarding magnetic force and magnetic intensity?

NUMS 2016
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

What is the dimension of magnetic field

A circuit in which there is a current of 5 amp is changed so that the current falls to zero in 0.1 s. If an average e.m.f of 200 volts is induced, what is the self inductance of the circuit?

NTS 2016 SMBBMC
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

A force which is experienced in a magnetic field depends on:

NTS 2011
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

A 3-cm length of wire is moved at right angles across a uniform magnetic field with a speed of 2.0 m/s . If the flux density is 5.0 teslas, what is the magnitude of the induced e.m.f?

NTS 2016 DUHS & JSMU
Physics
Magnetism and Electromagnetic Induction
Elimination Tool:

When the ohmmeter measures the infinite resistance, its pointer lies at

If the direction of current in two parallel wires is In opposite direction, then the wires will: