To demonstrate the phenomenon of interference, we require two sources which emit radiation
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(a) Of the same frequency and having a define phase relationship |
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(b) Of nearly the same frequency |
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(c) Of the same frequency |
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(d) Of different wavelengths |
(a) Of the same frequency and having a define phase relationship
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The two metallic plates of radius r are placed at a distance d apart and its capacity is C. If a plate of radius r/2 and thickness d of dielectric constant 6 is placed between the plates of the condenser, then its capacity will be
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(a) 7C/2 |
(b) 3C/7 |
(c) 7C/3 |
(d) 9C/4 |
Condenser A has a capacity of 15μF when it is filled with a medium of dielectric constant 15. Another condenser B has a capacity of 1 μF with air between the plates. Both are charged separately by a battery of 100 V. After charging, both are connected in parallel without the battery and the dielectric medium being removed. The common potential now is
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(a) 400 V |
(b) 800 V |
(c) 1200 V |
(d) 1600 V |
There is an electric field E in X-direction. If the work done on moving a charge 0.2 C through a distance of 2 m along a line making an angle 60° with the X-axis is 4.0, what is the value of E
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(a) |
(b) 4 N/C |
(c) 5 N/C |
(d) None of these |
A charge of magnitude 3e and mass 2m is moving in an electric field 
. The acceleration imparted to the charge is
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(a) 2Ee/3m |
(b) 3Ee/2m |
(c) 2m/3Ee |
(d) 3m/2Ee |
A achromatic combination is made with a lens of focal length f and dispersive power ω with a lens having dispersive power of 2ω. The focal length of second will be
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(a) 2f |
(b) f/2 |
(c) -f/2 |
(d) – 2 f |
If current flowing through shell of previous objective is equal to i, then energy density at a point distance 2R from axis of the shell varies according to the graph
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(a)
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(b)
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(c)
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(d)
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Cathode rays are similar to visible light rays in that
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(a) They both can be deflected by electric and magnetic fields |
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(b) They both have a definite magnitude of wavelength |
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(b) They both have a definite magnitude of wavelength |
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(d) They both can expose a photographic plate |
