Advertisements
Advertisements
प्रश्न
Consider the plane S formed by the dipole axis and the axis of earth. Let P be point on the magnetic equator and in S. Let Q be the point of intersection of the geographical and magnetic equators. Obtain the declination and dip angles at P and Q.
Advertisements
उत्तर
Let point P is in the plane, S needle is in north, so the declination is zero.
Q is the point of intersection between geographical meridian and magnetic meridian. So angle dip at P and Q will be zero with horizontal as magnetic middle stay horizontally.
As angle between axis of rotation of earth and magnetic axis is 11.3° and their respective equators are at 90° with their respective axis.
From figure,
For point P: Since point P lies in plane S formed by the dipole axis and the axis of the Earth, declination is zero.
For point Q: Since point Q lies on the magnetic equator, angle of dip is zero. Thus the angle of declination is 11.3°.
APPEARS IN
संबंधित प्रश्न
A compass needle, free to turn in a vertical plane orients itself with its axis vertical at a certain place on the earth. Find out the values of (i) horizontal component of earth's magnetic field and (ii) angle of dip at the place.
A conducting rod held horizontally along East- West direction is dropped from rest from a certain height near the Earth’s surface. Why should there be an induced emf across the end of the rod? Draw a plot showing the instantaneous variation of emf as a function of time from the instant it begins to fall.
A horizontal straight wire of length L extending from east to west is falling with speed v at right angles to the horizontal component of Earth’s magnetic field B.
(i) Write the expression for the instantaneous value of the e.m.f. induced in the wire.
(ii) What is the direction of the e.m.f.?
(iii) Which end of the wire is at the higher potential?
Can the earth's magnetic field be vertical at a place? What will happen to a freely suspended magnet at such a place? What is the value of dip here?
The reduction factor K of a tangent galvanometer is written on the instrument. The manual says that the current is obtained by multiplying this factor to tan θ. The procedure works well at Bhuwaneshwar. Will the procedure work if the instrument is taken to Nepal? If there is same error, can it be corrected by correcting the manual or the instrument will have to be taken back to the factory?
A compass needle which is allowed to move in a horizontal plane is taken to a geomagnetic pole. It ______.
The horizontal component of the earth's magnetic field at a place is `1/sqrt(3)` time the vertical component. Determine the angle of dip at that place.
State Tangent Law in magnetism.
Answer the following question in detail.
Define the Angle of Dip.
What happens to the angle of dip as we move towards magnetic pole from magnetic equator?
The earth’s magnetic field varies from point to point in space. Does it also change with time? If so, on what time scale does it change appreciably?
The earth may have even reversed the direction of its field several times during its history of 4 to 5 billion years. How can geologists know about the earth’s field in such distant past?
A magnetic needle free to rotate in a vertical plane parallel to the magnetic meridian has its north tip pointing down at 22° with the horizontal. The horizontal component of the earth’s magnetic field at the place is known to be 0.35 G. Determine the magnitude of the earth’s magnetic field at the place.
A telephone cable at a place has four long straight horizontal wires carrying a current of 1.0 A in the same direction east to west. The earth’s magnetic field at the place is 0.39 G, and the angle of dip is 35°. The magnetic declination is nearly zero. What are the resultant magnetic fields at points 4.0 cm below the cable?
Which of the following is responsible for the earth’s magnetic field?
Which of the following independent quantities is not used to specify the earth’s magnetic field?
If the change in value of g at height h above the surface of the earth is the same as at a depth d below the surface of the earth, when both d and h are much smaller than the radius of the Earth, then which one of the following is true?
At a place of latitude 5°, angle of dip is nearly
At a certain place horizontal component is `sqrt(3^2)` time the vertical component. The angle of dip at this place.
Let the magnetic field on earth be modelled by that of a point magnetic dipole at the centre of earth. The angle of dip at a point on the geographical equator ______.
- is always zero.
- can be zero at specific points.
- can be positive or negative.
- is bounded.
