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Explain dynamo effect?

Important Questions on Electromagnetic Induction

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The total intensity of the earth's magnetic field at equator is 5 units. What will be its value at the poles?
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The plane of a dip circle is set in the geographic meridian and the apparent dip is δ1. It is then set in a vertical plane perpendicular to the geographic meridian. The apparent dip angle is δ2. The declination θ at the place is
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The dip angle at point, P on earth's surface, is 45°. If the dip angle is changed by 1% then the change in the horizontal component of earth's magnetic field is:

 

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Which of the following demonstrated that earth has a magnetic fied:
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The earth's magnetic field was flipped by 180° a million years ago. This flip was relatively rapid and took 105 years. Then the average change in orientation per year during the flip closest to
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The magnetic field and angle of dip at a place on the earth are 0.3 G and 30°, respectively. The value of vertical component of the earth’s magnetic field at the place is _____.
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The strength of earth's magnetic field on the earth's surface is of the order: of
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A compass needle oscillates 20 times per minute at a place where the dip is 45° and the magnetic field is B1. The same needle oscillates 30 times per minute at a place where the dip is 30° and magnetic field is B2. Then B1:B2 is
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The relation between Bv, Bh and B is _____
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What is the angle of dip at a place where the horizontal component BH and vertical component BV of earth's magnetic field are equal:
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The strength of the Earth’s magnetic field is
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Earth's magnetic field has a horizontal component except at
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The horizontal component of the earth's magnetic field at a place is 0.25×10-4Wb/m2 and its vertical component is 0.35×10-4Wb/m-4. Then the earth's total magnetic field at that place is
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The vertical component of the earth's magnetic field is 6×10-5 T at any place where the angle of dip is 37°. The earth's resultant magnetic field at that place will be (Given tan37°=34)
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A rigid wire loop of square shape having side of length L and resistance R is moving along the x-axis with a constant velocity v0 in the plane of the paper. At t=0, the right edge of the loop enters a region of length 3L where there is a uniform magnetic field B0 into the plane of the paper, as shown in the figure. For sufficiently large v0, the loop eventually crosses the region. Let x be the location of the right edge of the loop. Let v(x), I(x) and F(x) represent the velocity of the loop, current in the loop, and force on the loop, respectively, as a function of x. Counter-clockwise current is taken as positive.

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Which of the following schematic plot(s) is(are) correct ? (Ignore gravity)
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The horizontal component of the earth's magnetic field is 3.6×10- tesla where the dip angle is 60°. The magnitude of the earth's magnetic field is,
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If BH=4×10-5 T and Bv=2×10-5 T, then the Earth's total field at the place is (in T):
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A Jet plane is travelling west at 450 metres per second. If the horizontal component of Earth's magnetic field is 4×10-4 Tesla and angle of dip is 30°, Then the vertical component is
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If θ1 and θ2 be the apparent angles of dip observed in two vertical planes at right angles to each other, then the true angle of dip θ is given by