Call me

Have a Query? We will call you right away.

+91

E.g: 9876543210, 01112345678

We will give you a call shortly, Thank You

Office hours: 9:00 am to 9:00 pm IST (7 days a week)

What are you looking for?

Syllabus

Define magnetic elements of earth?

WAT IS RETENTIVITY AND COERCIVITY

REPLY AS FAST AS POSSIBLE

1) An electron and proton moving parallel to each other in the same direction with equal momentum enter into a uniform magnetic field which is at right angle to thier velocites trace their trajectories in the magnetic field.

what is the principle of moving coil galvanometer?

Horizontal component of earth's magnetic field at a place is root 3 times its vertical component . what is the value of angle of dip at the place ?

Why do magnetic field lines always form closed loops?

what is the si unit of permeability. what do Tm/A stands for?

A 2MeV proton is moving perpendicular to a uniform magnetic field of 2.5 Tesla the force on the proton is ?

what is difference between diamagnetic paramagnetic and ferromagnetic?atleast 10 points.

what are eddy currents and its applications???

The susceptibility of a magnetic material is 0.9853. Identify the type of the magnetic material.Draw the modification of field pattern on keeping piece of this material in a uniform magnetic field.

Derive expression for magnetic dipole moment of an electron revolving around a nucleus

Give 5 differences between a bar magnet and a solenoid with their diagrams?

Q.38. If the period of oscillation of freely suspended bar magnet in earth's horizontal field H is 4 sec. When another magnet is brought near it, the period of oscillation is reduced to 2s. The magnetic field of second bar magnet is

(a) 4H

(b) 3H

(c) 2H

(D) $\sqrt{3}H$

a jet plane is travelling west at 450 ms^{-1}. if the horizontal component of earth's magnetic field at that place is 4 * 10^{-4}Tesla and the angle of dip is 30 degrees, find the emf induced between the ends of the wings having span of 30 m.Working of Cyclotron?

(a) 250 J (b) 200 J (c) 150 J (d) 10 J

a) 2.4N

b) 1.2N

c) 0.6N

d) 0.3N

A thin bar magnet is cut into two equal parts.the ratio of moment of inertia to the magnetic moment of each part will become?(as compare to original magnet)

solution please.

options-1) 1/2

2)1/4

3)1/8

4)1

Q. In the given diagram an electron is given a speed v at P towards A then time after which it comes out of the magnetic field B m is the mass of electron-

$1.\frac{m\mathrm{\pi}}{2eB}\phantom{\rule{0ex}{0ex}}2.\frac{2m\mathrm{\pi}}{eB}\phantom{\rule{0ex}{0ex}}3.\frac{3m\mathrm{\pi}}{4eB}$

4. It will never come out of the magnetic field

what do you mean by current sensitivity of a moving coil galvanometer ?on what factors does it depends?

two identical charged particles moving with same speed enter a region of uniform magnetic field. if one of these enters normal to the feild direction and the other along a direction at 30'c with the field , what would be the ratio of their angular frequencies?

The horizontal component of earth 's magnetic field at a place is B and angle of dip is 60 degrees. What is the value of vertical component of earth 's magnetic field at equator?

This question was asked in 2012 boards.I asked ths question yesterday also and the answer given by you is different from that available on this site where question-answers of previous year board papers are given.

there the answer is given to be zero and i don't undestand how. please review the question and explain how the vertical component of earth's magnetic field is zero at equator.

thank you

Which substance obeys Curie's Law ; feromagnetic or paramagnetic or both of them? give reason ,why they obey this law?

if a magnet is suspended at an angle 30 degree to the magnetic meridian the dip needle makes angle of 45 degree with the horizontal. the real dip is ??

^{-5}Wb in a bar of iron of cross section 0 .2 cm^{2}. Calculate the Permeability and Susceptibility of the bar ?true value of dip at a place is 45 degree.the plane of the dip circle is turned through 60 degree from the magnetic meridian.find apparent value of dip?please explain me the question with the help of figure a and give its solution.

34. A circular coil of diameter of 0.2m with 100 turns, carries a current of 1.2A. Find the magnetic field

(a) at the centre of coil,

(b) at a point distance 20 cm from centre on the axis.

The difference between the Gauss law of magnetism and electrostatics is that magnetic monopole doesnâ€™t exist.???how ??

Two magnets of magnetic moments M and 3

^{1/2 }M are joined to form a cross. The combination is suspended in a uniform magnetic field B. The magnetic moment M now makes an angle Î¸ with the field direction. find the value of angle Î¸.why is calcium listed as paramagnetic even though it has no unpaired electron ??

why a galvanometer is not used to measure current in a given circuit?

A wheel with 8 metallic spokes each 50cm long is rotated with a speed of 120rev./min . The earth's magnetic field at the place is 0.4G and the angle of dip is 60 . Calculate the emf induced between the axle and the rim of the wheel. How will the value of emf be affected if the number of spokes were increased ?

(1) Low hysteresis loss and low permeability

(2) Low hysteresis loss and high permeability

(3) High hysteresis loss and low permeability

(4) High hysteresis loss and high permeability

Sol. Answer (2) 3

What is benifit of high permeability of electrical machines

1) If the coil is free to rotate about x axis torque on coil is given by 1/2iAB0icap

2)if the coil is free to rotate about y axis torque on the coil is given by -1/2iAB0j cap

3) resultant force on coil is zero

4)equation for torque μ vector cross B vector where μ is magnetic moment of coil is not valid on coil if any of the side is fixed as axis

in what respect is a toroid different from a solenoid ? draw and compare the pattern of magnetic field lines in the 2 cases

Why is diamagnetism independent of temperature?

Apparent dips when dip circle is placed in two mutually perpendicular directions are 30 and 45 degree.What is actual dip at that place???

Q. Calculate the moment of the couple required to keep a bar magnet of moment 200 C.G.S units in a uniform magnetic field of 0.39 Oersted at an angle of 30$\xb0$ with the direction of the field.

A rod of length L, along East-West direction is dropped from a height H.

if B be the magnetic field due to earth at that place and angle of dip isx, then what is the magnitude of induced emf across two ends of the rodwhen the rod reaches the earth?A charge Q moving in a straight line is accelerated by a potential difference V.it enter a uniform magnetic field B perpendicular to its path.

Deduse in terms of B an expearence radius of circular path which is travels

(1)the north pole of one faces the south pole of the other

(2)the north pole of one faces the north pole of the other

Write the expression for the magnetic moment due to a planar square loop of side ‘

l’ carrying a steady current I in a vector form.In the given figure this loop is placed in a horizontal plane near a long straight conductor carrying a steady current I

_{1}at a distancelas shown. Give reason to explain that the loop will experience a net force but no torque. Write the expression for this force acting on the loop.a magnetic needle free to rotate in a vertical plane, orients itself vertically at a certain place on earth. what are the values of horizontal component of earth's mag field and angle of dip at that place?

the critical angle for glass air interface is ic. will the critical angle for glass water interface be greater than or less than ic ? why?

A dip ciccle shows an apparent dip of 60 degree at a place where the true dip is 45 degree. if the dip circle is rotated throgh 90 degree, what apparent dip will it show? first of all please tell me what is the meaing of apparent dip.how can a dip be apparent? it should always be true dip?

an element delta l=delta x l is placed at the origin and carriersa current I=2A.find out magnetic field at point P on y axis at distance of 1.0m due to element delta x=1cm.give also direction of field produced?

why does a freely suspended magnet always points along north- south direction. ?

(3) Diamagnetic substances

(2) Plastic (4) Iron

Sol. Answer (4) but why????

two identical loops,one of copper and another of constantan are removed from a magnetic field within same interval of time,in which loop the induced current will be greater ?

When a paramagnetic substance is placed in a uniform magnetic field, the magnetic field lines?

A closely wound solenoid of 2000 turns and area of cross-section 1.6 × 10

^{−4}m^{2}, carrying a current of 4.0 A, is suspended through its centre allowing it to turn in a horizontal plane.(a) What is the magnetic moment associated with the solenoid?

(b) What is the force and torque on the solenoid if a uniform horizontal magnetic field of 7.5 × 10

^{−2}T is set up at an angle of 30º with the axis of the solenoid?A ball of mass m is tied with two strings of equal length on a rod !!! If the rod is rotated with angular velocity w ( omega ) , then ------(1) T1 = T2........(2) T2 is more than T1......(3) T1 is more than T2.......(4) T1 = T2 / 6 ..............(NOTE ----- T1 AND T2 ARE THE TENSIONS OF STRING 1 AND 2 RESPECTIVELY !!! ) KINDLY HELP !!!

a coil of 40 ohm resistance, 100 turns and radius 6mm is connected to ammeter of resistance 160 ohm. coilis placed perpendicular to the magnetic field. when coil is taken out of the field 32 microcoulomb charge flows through it. the magnetic flux density is:

distinguish the magnetic properties of dia, para and ferromagnetic substances in term of,

(a) susceptibility

(b) magnetic permeability

(c) coercivity

2)) along its length ????

°. What is the value of vertical component of earth’s magnetic field at this place?What is Dip Circle? Explain its working.

charged

field out of system

uniformly charged

rotating with angular

velocity $\omega $

in ring i

Please answer urgently :

26.The following figure shows the variation of intensity of magnetisation versus the applied magnetic field intensity, Hj for two magnetic materials A and B:

(a) Identify the materials A and B.

(b) Why does the material B have a larger susceptibility than A for a given field at constant temperature?

1. Give reason: electric lines of force do not form closed loop while magnetic field lines form closed loop.2. Why do like poles repel each other and unlike poles attract each pole ? Give satisfactory reason.