Explanation:
The intensity of emitted light increase with the foreword current more the light intensity.
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The angle of dip at the magnetic equator is
| (a) 0° | (b) 45° | (c) 30° | (d) 90° |
A molecule with a dipole moment p is placed in an electric field of strength E. Initially the dipole is aligned parallel to the field. If the dipole is to be rotated to be anti-parallel to the field, the work required to be done by an external agency is
|
(a) – 2pE |
(b) – pE |
(c) pE |
(d) 2pE |
When the number of turns in a coil is doubled without any change in the length of the coil, its self inductance becomes
|
(a) Four times |
(b) Doubled |
(c) Halved |
(d) Unchanged |
A beam with wavelength 
falls on a stack of partially reflecting planes with separation d. The angle q that the beam should make with the planes so that the beams reflected from successive planes may interfere constructively is (where n = 1, 2, ……)
|
(a) |
(b) |
(c) |
(d) |
Nuclear fusion is common to the pair
|
(a) Thermonuclear reactor, uranium based nuclear reactor |
|
(b) Energy production in sun, uranium based nuclear reactor |
|
(c) Energy production in sun, hydrogen bomb |
|
(d) Disintegration of heavy nuclei, hydrogen bomb |
The torque acting on a dipole of moment 
in an electric field 
is
|
(a) |
(b) |
(c) Zero |
(d) |
In a radioactive decay, neither the atomic number nor the mass number changes. Which of the following would be emitted in the decay process
|
(a) Proton |
(b) Neutron |
(c) Electron |
(d) Photon |
64 drops each having the capacity C and potential V are combined to form a big drop. If the charge on the small drop is q, then the charge on the big drop will be
|
(a) 2q |
(b) 4q |
(c) 16q |
(d) 64q |
