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Photoelectric effect

 

I wanted to to know that why the attraction of electrons towards the positive plate of the the CRT is not taken into account in the Einstein’s explanation of the photoelectric effect and only the velocity imparted by the striking photon is considered.

 

English: German-born theoretical physicist Alb...

Thanks!

 

Regards
Amit Singh
XII-B

Answer:

I request you to kindly read the story well. Every aspect is dealt in detail. Please go thoroughly through the text material or the link to photoelectric effect provided in this page.

 

 

Some Physicists and their contributions

Physicists outside India

 

  • Galileo – (formulated the basic law of falling bodies, constructed a telescope and discovered four moons revolving around Jupiter)

    Picture of Isaac Newton, Galileo Galilei and A...
    Picture of Isaac Newton, Galileo Galilei and Albert Einstein
  • Archimedes: Archimedes Principle and theory of floatation, Principle of levers)
  • Albert Einstein: Theory of relativity, (Special and General)
  • Isaac Newton: Laws of motion, The method of Calculus
  • Michael Faraday: Electromagnetic induction, dynamo

 

Physicists from India

 

    • CV Raman – (studied light scattering and discovered the Raman effect)
    • JC Bose – (pioneered the investigation of radio and microwave optics)
    • SN Bose –English: Satyendra Nath Bose in Paris 1925

      (worked out statistical method of handling bosons)

    • MN Saha – (best known for his development of the Saha equation, used to describe chemical and physical conditions in stars.)
    • HJ Bhabha (initiated nuclear research programs in India; carried out experiments in cosmic rays; calculated cross section for elastic electron-positron scattering)
    • Subramanyan Chandrasekhar:-Subrahmanyan Chandrasekhar in his later years

      (won the 1983 Nobel Prize for Physics for key discoveries that led to the currently accepted theory on the later evolutionary stages of massive stars. The Chandrasekhar limit is named after him.)

 

Relativity and shape of objects

A triangular shape spacecraft flies by an observer at 0.95c. When the ship is measured
by an observer at rest with respect to the ship, the distances x and y are found to be 50m and 25m respectively. What is the shape of the ship as seen by an observer who sees the ship in motion along the direction shown in figure?

 

Asked Mona

Doubt in Law of Gravitation

Newton's law of universal gravitation for two ...
Newton's law of universal gravitation for two bodies. This law governs gravitational forces in the Earth. (Photo credit: Wikipedia)
Colorized engraving after Enoch Seeman's 1726 ...

According to law of gravitation
F=g*(m1*m2)/r^2
If we bring two objects close to each other say our hands then the distance will be zero and the force of attraction will become infinite because r will we zero. Therefore F will become infinite but this is not the case.
When we touch our both palms together we can easily pull then away.

Asked Ankit Sharma

Answer

When we consider the distance, it is between the center of mass of the two bodies under consideration. When we bring our hands together the distance between their CM is not zero.

Other wise, the two particles under consideration must be point masses.

Then if you consider two atoms or two nuclei, the forces that come into play will be different if we decrease the distance between two atoms or nuclei. The attraction will turn into strong repulsion when the limits are exceeded.

 

on Einsteins research

Albert Einstein

if the papers of Einstein depend upon speed of light as its base, and the particles which have speed greater than the light could pose treat to be it. then in that case why cant that particle could be set as the Einsteins theorms base so that it doesnt violate and simple corrections could correct the theorms!!

(Sajin Asks)

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