Advertisements
Advertisements
प्रश्न
Mention the two features of x-ray spectra, not explained by classical electromagnetic theory.
Advertisements
उत्तर
Though classical electromagnetic theory suggests the emission of radiations from accelerating electrons, it could not explain two features exhibited by x-ray spectra. These features are given below
- For a given accelerating voltage, the lower limit for the wavelength of continuous x-ray spectra is the same for all targets. This minimum wavelength is called cut-off wavelength.
- The intensity of x-rays is significantly increased at certain well-defined wavelengths as shown in the case of characteristic x-ray spectra for molybdenum.
APPEARS IN
संबंधित प्रश्न
A photoelectric surface is illuminated successively by monochromatic light of wavelength λ and `λ/2`. If the maximum kinetic energy of the emitted photoelectrons in the second case is 3 times that in the first case, the work function of the material is
In photoelectric emission, a radiation whose frequency is 4 times threshold frequency of a certain metal is incident on the metal. Then the maximum possible velocity of the emitted electron will be
A light of wavelength 500 nm is incident on a sensitive metal plate of photoelectric work function 1.235 eV. The kinetic energy of the photoelectrons emitted is (Take h = 6.6 × 10–34 Js)
The work functions for metals A, B and C are 1.92 eV, 2.0 eV and 5.0 eV respectively. The metal/metals which will emit photoelectrons for a radiation of wavelength 4100Å is/are
Give the definition of intensity of light according to quantum concept and its unit.
What is a photocell?
List out the characteristics of photons.
Give the applications photocell.
How many photons of frequency 1014 Hz will make up 19.86 J of energy?
At the given point of time, the earth receives energy from the sun at 4 cal cm–2 min–1. Determine the number of photons received on the surface of the Earth per cm2 per minute. (Given: Mean wavelength of sunlight = 5500 Å)
