Advent Of Modern Physics Notes by Sir Waqar Hussain
Important Easy Notes of Physics of Chapter No. 17: Advent Of Modern Physics written by Professor Mr. Waqar Hussain Suib. These notes are very helpful in the preparation of Physics for students of the 12th class and these are according to the paper patterns of all Sindh Book Boards.
Summary and Contents:
Topics which are discussed in the notes are given below:
- Definition of Frame of reference with example
- Definition of Inertial frame of reference with example
- Definition of Transformation
- Definition of Galilean Transformation
- State and Explain Einstein’s Special Theory of Relativity
- CONSEQUENCES OF SPECIAL RELATIVITY: Mass Variation, Length Contraction, Time Dilation and Mass Energy Relation.
- Definition of Rest mass with its Notation
- Definition of Relativistic mass with its Notation
- Definition of Proper length with its Notation
- Definition of Relativistic length with its Notation
- Definition of Proper time with its Notation
- Definition of Relativistic time with its Notation
- Black Body Radiation and Quantum Theory
- Definition of Black body with its Construction
- Definition of Black body radiation and Intensity versus wave length graph
- Properties of black body radiation and Laws of Black body radiations
- State Wien’s displacement law with its Notation
- State Rayleigh jeans law with its Notation
- State Planks law with its Notation
- State and Explain Photo Electric Effect with its Explanation, Properties of photoelectrons, Effect Of Intensity, Effect Of Frequency, Laws of Photoelectric Effect, Einstein Explanation of photo electric Effect, Einstein’s Equation for Photoelectric Effect and Compton’s Effect.
- State and Explain De-Broglie Hypotheses with Mathematically
- State and Explain Heisenberg Uncertainty Principle
- State and Explain Pair production
- State and Explain Pair Annihilation
- Find the cut off wavelength for a given metal whose work function is 4.14eV.
- The work function of certain metal is 3.03eV. When this metal is illuminated by the
infrared light of 1.2x1015 Hz. Find the maximum kinetic energy of the emitted
photoelectrons.
- A 50 m trailer is moving with relativistic speed. It passes over a bridge of length 40m. To
an observer at rest with respect to the bridge at one instant, the trailer seems to overlap
the bridge i.e. the ends of the trailer seem to coincide with the ends of bridge. Find the
speed of the trailer.
- The work function of a photo emissive surface is 4.0eV. What will be the velocity of
fastest photoelectrons emitted from it by an accident light of frequency 3.0x1015Hz.
- The work function of metal is 2eV. The light of wavelength 3000 A° is made to fall on it.
Find the kinetic energy of the fastest emitted photoelectrons.
- Find the relativistic speed at which the kinetic energy of a particle of rest mass mo
becomes doubles its rest mass energy. Given mo = 1.67x10–27 Kg. Also calculate:
1) Rest mass energy
2) Kinetic energy
3) Total energy
- The range of visible light is 4000Ao to 7000Ao
. Will photoelectrons be emitted by a
copper surface of work function 4.4eV, when illuminated by visible light? Give the
mathematical proof of your answer.
- When the light of the wavelength 4000°A falls on a metal surface, stopping potential is
0.6 volt. Find the value of the work function of the metal.
- Find the speed at which the mass of a particle will be doubled.
- Given moc
2 = 0.511MeV. Find the total energy E and the kinetic energy K of an electron
moving with a speed v = 0.85c.
- If a neutron is converted entirely into energy, how much energy is produced? Express
your answer in joule and electron – volt.
- Sodium surface is shined with the light of wavelength 3 x 10–7m. If the work function of
Na=2.46eV, find the kinetic energy of the photoelectrons.
- A sodium surface is shined with the light of wavelength 3 x 10–7m, if the work function
of sodium is 2.46 eV, find the kinetic energy of the photoelectron.
- What minimum energy is required in an X-ray tube to produce X-rays with a
wavelength of 0.1 x 10–10m.
- Compare the energy of a photon of wavelength 2 x 10–6m with the energy of X-ray
photon of wavelength 2 x 10–10m.
- Estimate the relativistic mass and the wavelength associated with an electron moving
at 0.9c.
- An electron exists within a region of 10–10m, find its momentum uncertainty and
approximate kinetic energy.
- In Compton Scattering process the fractional change in wavelength of X-Rays Photon is
1% at an angle 120o
; find the wavelength of X – rays used in this experiment.
- Calculate the relativistic speed at which the mass of a particle becomes double its rest
mass
- A sodium surface is shined with the light of wavelength 3 x 10–7m, if the work function
of sodium is 2.46 eV, find the kinetic energy of the photoelectron and cutoff
wavelength.
- If the electron beam in a television picture tube is accelerated by 10,000 V what will
be the de Broglie’s wavelength? (h = 6.63 x 10–34 J.s., m = 9.1 x 10–31 kg).
- What will be the relative velocity and momentum of a particle whose rest mass is mo
and kinetic energy is equal to twice of its rest mass energy.
- If the electron beam in a television picture tube is accelerated by 10 kV. What will be
the de Broglie wavelength of an electron? (h = 6.63 x 10–34Js, m = 9.1 x 10–31 kg).
- Given moc
2=0.511 MeV. Find the total energy "E" and the kinetic energy K of an
electron moving with speed v=0.85c.mo= 9.1 x 10- 31 kg, c=3 x 108 m/s.
- A sodium surface is shined with the light of wavelength 3 x 10-7m, if the work function
of sodium is 2.46 eV, find the kinetic energy of the photoelectron and cutoff
wavelength. h=6.63x10-34 J-s, c =3 x 108m/s
- Pair annihilation occurred due to a head-on-collision of an electron and positron having
the same kinetic energy, produce pair of photons each having energy of 2.5 MeV. What
were their kinetic energies before collision? Given moc
2=0.511MeV.
- What will be the velocity and momentum of a particle whose rest mass is mo and kinetic
energy is equal to twice of its rest mass energy.
- In a TV picture tube, an electron is accelerated by a potential difference of 12000V.
Determine de-Broglie wavelength.
Given that (h = 6.63x10-34 J.s e=1.6x10 -19 C, me=9.11x10-31 kg).