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Define magnetic elements of earth?
WAT IS RETENTIVITY AND COERCIVITY
REPLY AS FAST AS POSSIBLE
what is the principle of moving coil galvanometer?
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?
Why do magnetic field lines always form closed loops?
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?
a jet plane is travelling west at 450 ms-1. if the horizontal component of earth's magnetic field at that place is 4 * 10-4Tesla 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?
Apparent dips when dip circle is placed in two mutually perpendicular directions are 30 and 45 degree.What is actual dip at that place???
what do you mean by current sensitivity of a moving coil galvanometer ?on what factors does it depends?
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
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.
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
a current is flowing in electricity line toward north,. the direction of magnetic field at a point which is just below the line is towards north or south or east or west?
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 ??
Two magnets of magnetic moments M and 31/2 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 θ with the field direction. find the value of angle θ.
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 ?
what is the si unit of permeability. what do Tm/A stands for?
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?
in what respect is a toroid different from a solenoid ? draw and compare the pattern of magnetic field lines in the 2 cases
A rod of length L, along East-West direction is dropped from a height H.
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
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 I1 at a distance l as 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?
why does a freely suspended magnet always points along north- south direction. ?
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?
A closely wound solenoid of 2000 turns and area of cross-section 1.6 × 10−4 m2, 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?
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.
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 ?
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
What is Dip Circle? Explain its working.
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.
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Syllabus
Define magnetic elements of earth?
7. A cylinder of mass M and radius 2R has a groove of radius R. A block Of
mass m is hung from the circumference of the cylinder and the cylinder
itself is hung from a rigid support by a thread wound on the groove as
shown in the figure.
If the acceleration of centre of mass of the cylinder is 'a1' acceleration of
the block is a2 downward and angular acceleration of the cylinder is
then relation between al, a2 and will be
WAT IS RETENTIVITY AND COERCIVITY
REPLY AS FAST AS POSSIBLE
what is the principle of moving coil galvanometer?
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?
Why do magnetic field lines always form closed loops?
A 2MeV proton is moving perpendicular to a uniform magnetic field of 2.5 Tesla the force on the proton is ?
(a) (b)
(c) (d)
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.
2.find displacement of particle after time t= 2πm/qB {ans=(2πmvo/qB)(i)}
3. find displacement of particle for any arbitrary time t. {ans= vot i+ (mvo/qB)sin(qBt/m) j + mvo/qB(cos(qBt/m)-1)k
pls explain how to do ???
Derive expression for magnetic dipole moment of an electron revolving around a nucleus
Q6. One end of a light spring of natural length d and spring constant k (= mg/d) is fixed on a rigid support and the other end is fixed to a smooth ring of mass m which can slide without friction on a vertical rod fixed at a distance d from the support. Initially, the spring makes an angle of 37° with the horizontal as shown in the figure.The system is released from rest. The speed of the ring at the same angle subtended downward will be
(A) (B)
(C) (D)
Give 5 differences between a bar magnet and a solenoid with their diagrams?
a jet plane is travelling west at 450 ms-1. if the horizontal component of earth's magnetic field at that place is 4 * 10-4Tesla 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?
Apparent dips when dip circle is placed in two mutually perpendicular directions are 30 and 45 degree.What is actual dip at that place???
a) 2.4N
b) 1.2N
c) 0.6N
d) 0.3N
what do you mean by current sensitivity of a moving coil galvanometer ?on what factors does it depends?
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
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.
20 Area of one side of each plate is A and separation between consecutive plates is d. Emf of the battery connected is V. The charge on plate 2 is .
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
a current is flowing in electricity line toward north,. the direction of magnetic field at a point which is just below the line is towards north or south or east or west?
(1) acceleration of m1 will be equal to zero
(2) acceleration of m2 will be downwards
(3) magnitude of acceleration of two blocks will be non-zero and unequal
(4) magnitude of acceleration of both the blocks will be
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 ??
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)
(1) µ ∝ n (2) µ ∝ 1/n (3) µ ∝ n2 (4) µ ∝ 1/n2
Two magnets of magnetic moments M and 31/2 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 θ with the field direction. find the value of angle θ.
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 ?
what is the si unit of permeability. what do Tm/A stands for?
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?
A pulley-block arrangement is shown in the adjacent figure, if accelerations of m1, m2 and m3 are a1, a2 and a3 respectively, then relation between a1, a2 and a3 is ( all strings and pulleys are ideal.)
(A) a2 - a3 + 10a1 =0 (B) a3-a2+10a1 =0
(C) a2-2a3+10a1 =0 (d) 2a2 + a3 + 5a1 =0
in what respect is a toroid different from a solenoid ? draw and compare the pattern of magnetic field lines in the 2 cases
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?pole of an electromagnetic are 10 Wb m–2 and 250 Am–1 respectively.
What is the relative permeability of iron ?(m0 = 4p × 10–7 Hm–1)
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
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 I1 at a distance l as 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.
1. 1/3 m 2. 1/2 m 3. 1/6 m 4. 1/8 m
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?
why does a freely suspended magnet always points along north- south direction. ?
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?
A closely wound solenoid of 2000 turns and area of cross-section 1.6 × 10−4 m2, 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?
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.
(1) (2) (3) (4) Zero
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 ?
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 !!!
Magnetic Dipole Moment
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:
Q. A square loop of side 'a' is made by a current carrying wire. What is its magnetic field at its vertex 'P'?
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 Dip Circle? Explain its working.
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?
Q. A metal rod of length 'L' and mass 'm' is pivoted at one end . A thin disk of mass 'M' and radius 'R' (<L) isattached at its center to the free end of the rod . Consider two ways the disc is attached : (case A) The disc is not free to rotate about its center and case B the disc is free to rotate about its center . The rod - disc system performs SHM in vertical plane agfter in vertical plane after being released from the same displaced position . Which of the following statements is are true ? (1) Restoring torque in case A = Restoring torque in case B (2) Restoring torque in case A < Restoring torque in case B (3) Angular frequency for case A > Angular frequency for case B (4) Angular frequency for case A < Angular frequency for case B
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.
1. A particle is rotating about a vertical axis in the horizontal plane such that the angular velocity of the particle about the axis is constant and is equal to 1 rad/s. Distance of the particle from axis is given by R=R0-t where t stands for time. The speed of the particle as a function of time is.