- AThermionic emission
- BField emission
- CPhotoelectric emission
- DAll of these
Explanation:
For electron emission energy is required. This energy can be supplied by Thermionic emission, field emission, photoelectric emission:
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An electron and a proton are at a distance of 1. The moment of this dipole will be (C X m)
|
(a) 1.6 |
(b) 1.6 |
(c) 3.2 |
(d) 3.2 |
A heater of 220 V heats a volume of water in 5 minute time. A heater of 110 V heats the same volume of water in
|
(a) 5 minutes |
(b) 8 minutes |
(c) 10 minutes |
(d) 20 minutes |
Wave which cannot travel in vacuum is
|
(a) X-rays |
(b) Infrasonic |
(c) Ultraviolet |
(d) Radiowaves |
If is the intensity of the principal maximum in the single slit diffraction pattern, then what will be its intensity when the slit width is doubled
|
(a) |
(b) |
(c) 2 |
(d) 4 |
Which of the transitions in hydrogen atom emits a photon of lowest frequency (n = quantum number)
|
(a) n = 2 to n = 1 |
(b) n = 4 to n = 3 |
(c) n = 3 to n = 1 |
(d) n = 4 to n = 2 |
Cathode rays consist of
|
(a) Photons |
(b) Electrons |
(c) Protons |
(d) α -particles |