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
When a metallic surface is illuminated with radiation of wavelength λ, the stopping potential is V. If the same surface is illuminated with radiation of wavelength 2λ, the stopping potential is `"V"/4`. The threshold wavelength for the metallic surface is
The threshold wavelength for a metal surface whose photoelectric work function is 3.313 eV is __________.
How does photocurrent vary with the intensity of the incident light?
How will you define threshold frequency?
Define stopping potential.
What is a surface barrier?
Briefly discuss the observations of Hertz, Hallwachs and Lenard.
Explain the quantum concept of light.
A 3310 Å photon liberates an electron from a material with energy 3 × 10−19 J while another 5000 Å photon ejects an electron with energy 0.972 × 10−19 J from the same material. Determine the value of Planck’s constant and the threshold wavelength of the material.
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)
