Question

Wavefront means

(a) All particles in it have same phase

(b) All particles have opposite phase of vibrations(c) Few particles are in same phase, rest are in opposite phase

(c) Few particles are in same phase, rest are in opposite phase

(d) None of these

Answer

(a) All particles in it have same phase

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A short magnet of moment 6.75 Am2 produces a neutral point on its axis. If horizontal component of earth's magnetic field is 5  , then the distance of the neutral point should be

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Charge is:

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List I

(Position of the object)

List II

(Magnification)

(I) An object is placed at focus before a convex mirror

(A) Magnification is -

(II) An object is placed at centre of curvature before a concave mirror

(B) Magnification is 0.5

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(E) Magnification is 0.33

Codes :

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(c) I-C, II-B, III-A, IV-E

(d) I-B, II-E, III-D, IV-C

A narrow beam of white light goes through a slab having parallel faces.
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(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.

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Black hole is a

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