What is rest mass of photon?

By nature, photons are just energy packets which are travelling continuously. Therefore photons have zero rest mass as they are never stationary. Note-According to Einstein's quantum theory light propagates in the form of packets i.e. quanta of energy, which is called photon. The rest mass of photons is being zero. It can be shown, according to the relativity theory of light. According to the relativistic theory equation, the mass of the photon is computed as: m = m 0 1 − ( c 2 / v 2 ) m 0 = m 1 − ( c 2 / v 2 ) when v = 0 ; So m 0 = 0 Where m 0 is the rest mass of the Photon .

E M B I B E

A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 20 - Bohr Model, X-Ray Spectra, Wave-Particle Duality>EXERCISE 20>Q 15

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12th West Bengal Board

IMPORTANT

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In hydrogen atom, the electron is revolving in the third orbit. What will be its angular momentum?

Important Questions on Bohr Model, X-Ray Spectra, Wave-Particle Duality

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12th West Bengal Board

IMPORTANT

A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 20 - Bohr Model, X-Ray Spectra, Wave-Particle Duality>EXERCISE 20>Q 16

State Bohr's postulates regarding the structure of hydrogen atom.

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12th West Bengal Board

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A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 20 - Bohr Model, X-Ray Spectra, Wave-Particle Duality>EXERCISE 20>Q 17

How many quanta of different energy can be emitted by a hydrogen atom if the electron is in the third orbit? - Justify.

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12th West Bengal Board

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A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 20 - Bohr Model, X-Ray Spectra, Wave-Particle Duality>EXERCISE 20>Q 18

The spectrum of sodium atom should have similarly with that of hydrogen. In what sense is this true?

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12th West Bengal Board

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A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 20 - Bohr Model, X-Ray Spectra, Wave-Particle Duality>EXERCISE 20>Q 19

What is the difficulty of classical theory of revolving electric charge in a hydrogen atom?

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12th West Bengal Board

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A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 20 - Bohr Model, X-Ray Spectra, Wave-Particle Duality>EXERCISE 20>Q 20

Hydrogen atom has one electron. How many lines are originated in hydrogen spectrum.

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12th West Bengal Board

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A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 20 - Bohr Model, X-Ray Spectra, Wave-Particle Duality>EXERCISE 20>Q 21

The value of ground state energy of hydrogen atom is $- 13.6 eV$ . What does the negative sign signify?

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12th West Bengal Board

IMPORTANT

A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 20 - Bohr Model, X-Ray Spectra, Wave-Particle Duality>EXERCISE 20>Q 21

The value of ground state energy of hydrogen atom is $- 13.6 eV$ . How much energy is required to take an electron in this atom from the ground state to the first excited state?

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12th West Bengal Board

IMPORTANT

A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 20 - Bohr Model, X-Ray Spectra, Wave-Particle Duality>EXERCISE 20>Q 22

Why are Bohr's orbits called 'stationary orbits'?