Advertisements
Advertisements
प्रश्न
What is a surface barrier?
Advertisements
उत्तर
- To leave the metallic surface, the free electrons must cross a potential barrier created by the positive nuclei of the metal.
- The potential barrier which prevents free electrons from leaving the metallic surface is called the surface barrier.
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 __________.
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.
List out the laws of photoelectric effect.
Explain experimentally observed facts of the photoelectric effect with the help of Einstein’s explanation.
Give the applications photocell.
How many photons per second emanate from a 50 mW laser of 640 nm?
Calculate the energies of the photons associated with the following radiation:
- violet light of 413 nm
- X-rays of 0.1 nm
- radio waves of 10 m
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)
