Electron cannot exist in the nucleus it is confirmed by observing that______________?
(A) It does emit radiation
(B) Its size as compare to proton and neutron is very small
(C) No antiparticle of electron is present
(D) The velocity of electron must be very high according to uncertainty principle
Wave-like characteristic of electron is demonstrated by______________?
(A) Line spectrum of atoms
(B) Production of x-rays.
(C) Diffraction by crystalline solids
(D) Photoelectric effect
UV radiation can be produced by______________?
(A) Heating the filament
(B) Electron excitation in the gas
(C) Ionization of atoms
(D) All the above
X-rays are diffracted by a crystal but not by a diffraction grating because_____________?
(A) The ions in a crystal are well arranged
(B) The lines in a diffraction grating cannot reflect X-rays.
(C) The penetration power of X-rays is high in a diffraction grating
(D) The wavelengths of X-rays are of the same order of magnitude as the separation between atoms in a crystal
Maximum frequency in the spectrum from X-ray tube is directly proportional to the______________?
(A) Number of incident electron i.e. filament current
(B) The kinetic energy of the incident electron i.e. the potential difference through which they are accelerated
(C) The soft target which can easily emit electrons
(D) All of above are correct
The minimum wavelength of X-rays produced by the bombardment of electrons on the screen of a television set where the accelerating potential is 2.0K V will be______________?
(A) 6.2 x 10-10m
(B) 9.1 x 10-18m
(C) 3.11 x 10-10m
(D) 4 x 10-10m
Which one of the following has the greatest energy gap ?
(A) insulator
(B) conductor
(C) semi conductor
(D) any of above
The velocity of an oscillating charge as it moves to and fro along a wire is always_____________?
(A) constant
(B) zero
(C) changing
(D) infinite
Identify the correct statement about minority carriers_____________?
(A) holes in n-type and free electrons in p-type
(B) holes in n-type and p-type
(C) free electrons in n-type and holes in p-type
(D) free electrons in n-type and p-type