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 .

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The electric potential between a proton and an electron is given by $V = V \ln \frac{r}{r_{0}}$ , where $r_{0}$ is a constant. Assuming Bohr's model to be applicable, write variation of $r_{n}$ with $n$ where $n$ is the principal quantum number

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

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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 52

A photon collides with a stationary hydrogen atom in ground state inelastically. Energy of the colliding photon is

10.2 eV .

After a time interval of order of microsecond another photon collides with the same hydrogen atom inelastically with an energy of

15 eV

. What will be absorbed by the detector?

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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 53

In the Bohr model of the hydrogen atom

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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 54

The ratio of their de-Broglie wavelength

\frac{λ_{e}}{λ p}

is when an electron of mass

m_{e}

and a proton of mass

m_{p}

are moving with the same speed.

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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 55

The ratio of the de-Broglie wavelength associated with these particles, when an electron and a proton are moving in the same direction with same kinetic energy.

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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 56

α

-particle and a proton are accelerated from rest by a potential difference of

100 V

. After this their de-Broglie wavelength are

λ_{α}

and

λ_{p}

respectively. The ratio

\frac{λ_{p}}{λ_{e}}

, to the nearest integer is

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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 57

The de-Broglie wavelength of the electron in the ground state of the hydrogen atom is (Radius of the first orbit of hydrogen atom

= 0.53 \vec{A}

)

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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 58

For the Bohr's second orbit of circumference

2 π r

, the deBroglie wavelength of revolving electron will be

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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 59

If an electron and a photon propagate in the form of waves having the same wavelength, it implies that they have the

The electric potential between a proton and an electron is given by V=Vlnrr0, where r0 is a constant. Assuming Bohr's model to be applicable, write variation of rn with n where n is the principal quantum number

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

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The electric potential between a proton and an electron is given by $V = V \ln \frac{r}{r_{0}}$ , where $r_{0}$ is a constant. Assuming Bohr's model to be applicable, write variation of $r_{n}$ with $n$ where $n$ is the principal quantum number