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प्रश्न
Choose the correct option.
A place where the horizontal component of Earth's magnetic field is zero lies at
पर्याय
geographic equator
geomagnetic equator
one of the geographic poles
one of the geomagnetic poles
उत्तर
A place where the horizontal component of Earth's magnetic field is zero lies at one of the geomagnetic poles.
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संबंधित प्रश्न
Name three elements of the earth's magnetic field which help in defining earth's magnetic field completely.
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To keep valuable instruments away from the earth's magnetic field, they are enclosed in iron boxes. Explain.
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.
Choose the correct option.
A place where the vertical components of Earth's magnetic field is zero has the angle of dip equal to
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Answer the following question regarding earth’s magnetism:
The angle of dip at a location in southern India is about 18°. Would you expect a greater or smaller dip angle in Britain?
Answer the following question regarding earth’s magnetism:
If you made a map of magnetic field lines at Melbourne in Australia, would the lines seem to go into the ground or come out of the ground?
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?
Interstellar space has an extremely weak magnetic field of the order of 10–12 T. Can such a weak field be of any significant consequence? Explain.
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.
At a certain location in Africa, a compass points 12° west of the geographic north. The north tip of the magnetic needle of a dip circle placed in the plane of magnetic meridian points 60° above the horizontal. The horizontal component of the earth’s field is measured to be 0.16 G. Specify the direction and magnitude of the earth’s field at the location.
A short bar magnet of magnetic moment 5.25 × 10−2 J T−1 is placed with its axis perpendicular to the earth’s field direction. At what distance from the centre of the magnet, the resultant field is inclined at 45° with earth’s field on (a) its normal bisector and (b) its axis. Magnitude of the earth’s field at the place is given to be 0.42 G. Ignore the length of the magnet in comparison to the distances involved.
Which of the following statements about earth's magnetism is correct?
A long straight horizontal cable carries a current of 2.5 A in the direction 10° south of west to 10° north of east. The magnetic meridian of the place happens to be 10° west of the geographic meridian. The earth’s magnetic field at the location is 0.33 Gauss, and the angle of dip is zero. Locate the line of neutral points. (Ignore the thickness of the cable).
The vertical component of earth’s magnetic field at a place is √3 times the horizontal component the value of angle of dip at this place is ______.
At a given place on earth’s surface the horizontal component of earth’s magnetic field is 2 × 103-5 T and resultant magnetic field is 4 × 103-5 T. The angle of dip at this place is ______.
The net magnetic flux through any closed surface, kept in a magnetic field is ______.
The small angle between magnetic axis and geographic axis at a place is ______.
Assertion(A): A magnetic needle free to rotate in a vertical plane, orients itself (with its axis) vertical at the poles of the earth.
Reason (R): At the poles of the earth the horizontal component of earth’s magnetic field will be zero.
Select the most appropriate answer from the options given below:
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?
The vertical component of earth's magnetic field is zero at a place where angle of dip is
At a place of latitude 5°, angle of dip is nearly
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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.
