F.E. (Semester – I),APPLIED SCIENCE – I (Physics),2011 Question Paper,University Of Pune Question Paper

University Of Pune Question Paper
F.E. (Semester – I) Examination, 2011
APPLIED SCIENCE – I
(Physics) (2008 Pattern)
Time : 2 Hours Max. Marks : 50
Instructions : 1) Neat diagrams must be drawn wherever necessary.
2) Black figures to the right indicate full marks.
3) Use of logarithmic tables, slide rule, Mollier charts, electronic
pocket calculator and steam tables is allowed.
4) Assume suitable data if necessary.
1. a) Obtain the equation of path difference between the reflected rays when the
monochromatic light is incident on the uniform thickness film. Give the
conditions of minimum and maximum. 7
b) Explain refraction of electron when it travels from low potential region to high
potential region and explain electrostatic lens. 6
c) When a thin transparent plate of thickness 6.3 × 10–4 cm is introduced in the
path of one of the interfering rays of Michelson’s interferometer then a central
bright fringe shifts to a position previously occupied by 6th bright fringe. If
the wavelength of light is 5460 A°, find the refractive index of the plate. 4
OR
2. a) Explain construction and working of Bainbridge mass spectrograph and prove
that different isotopes follow a circular path of different radius. 7
b) In Newton’s ring’s experiment, show that the diameters of dark rings are
proportional to square root of natural numbers. 6
c) An electron accelerated from rest through a potential difference of 900 V,
enters a uniform perpendicular magnetic field of flux density 0.01 Tesla.
Determine the linear velocity of electron and radius of circular path followed
by electron in mag. field. Given me = 9.1 × 10–31 kg, e = 1.6 × 10–19 C. 4
3. a) With the help of circuit diagram explain how magneto-striction effect is used
in oscillator circuit to generate ultrasonic waves. 6
b) What is diffraction grating ? Give the equation of resultant intensity of light
with the meaning of each symbol, when monochromatic light is diffracted
from grating. Obtain the equation of maxima and minima. 6
[3961] – 103
c) A single slit Fraunhoffer’s diffraction pattern is formed using white light. For
what wavelength of light does the second minimum will coincide with third
minimum of light of wavelength 4000 A°. 4
OR
4. a) What is diffraction of light ? What are the types of diffraction ? Distinguish
between them. 6
b) Explain echo sounding and cavitation techniques as an application of ultrasonic
waves. 6
c) A grating has 6000 lines per cm. If the monochromatic light of wavelength
4500 A° is diffracted from it, how many orders can be seen ? If another
grating having 7000 lines per cm is used, what is the effect on number of order
seen ? 4
5. a) What is polarization by double refraction ? Explain it on the basis of Huygen’s
theory. What is positive and negative crystals ? 7
b) What is nuclear chain reaction in fission ? Why it is not possible in natural
uranium ? Discuss how it is made possible. 6
c) The protons in a cyclotron describes a circular path of radius 0.4 m just
before emerging from the dees. If the magnetic flux density is 1.5 Tesla, what
is the maximum kinetic energy of protons and frequency of applied AC voltage
between the dees ?
(Given : mp = 1.67 × 10–27 kg)
 q = 1.6 × 10–19C 4
OR
6. a) Explain principle, construction and working of Betatron and derive the equation
of Betatron condition. 7
b) Explain how to analyze the given beam of light as a unpolarized, plane,
elliptically ,circularly and partially polarized with the help of Nicol prism and
quarter wave plate. 6
c) A retardation plate of thickness 2.275 × 10–3 cm is cut with its faces parallel to
optic axis. If the emergent beam of light is elliptically polarized find the
wavelength of monochromatic light incident normally on it.
(Given 1 . .586, 1 592 μo = μe = ). 4
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F. E. (Semester – II),2014 Question Paper,APPLIED SCIENCE – II (Physics),University Of Pune Question Paper

University Of Pune Question Paper F. E. (Semester – II) Examination, 2014 APPLIED SCIENCE – II (Physics) (Old) (2008 Course) Time : 2 Hours Max. Marks : 50 Instructions : 1) Answer any three questions (Q.1 or Q.2, Q.3 or Q.4, Q.5 or Q.6) 2) Figures to the right indicate full marks. 3) Neat diagrams must be drawn wherever necessary. 4) Use of electronic calculator is allowed. 5) Assume suitable data if necessary. Constants : 1) Mass of electron (me) = 9.1 × 10–31kg. 2) Charge on electron (e) = 1.9 × 10 –19 C 3) Mass of neutron =(mn) = 1.675 × 10–27kg. 4) Plank’s Constant (h) = 6.63 × 10–34 J.s 5) Velocity of light in vacuum (c) = 3 × 108 m/s. 1. a) State and explain Heisenberg’s Uncertainty Principle. Illustrate this principle with an experiment on diffraction of electrons. 7 b) Derive Schrodinger’s time independent equation. 6 c) Calculate the de-Broglie wavelength associated with 1 Mev neutron. 4 OR 2. a) Derive equation of energy and wave function when a free particle is trapped in an infinite potential well. 7 b) Explain the concept of group velocity. Show that group velocity is equal to the velocity of the particle. 6 c) Calculate energy level difference between first two excited state of a neutron trapped in infinite potential well of width 10–15 m. 4 3. a) With the help of energy level diagram explain construction and working of He-Ne laser. 6 b) What is Critical Magnetic Field ? Explain Type–I and Type–II superconductors. 6 c) Explain for laser (a) Stimulate emission of radiation (b) Pumping. 4 OR 4. a) What is superconductivity ? Explain BCS theory of superconductivity. 6 b) With the help of energy level diagram explain construction and working of Ruby laser. 6 c) Explain for superconductor (a) Transition temperature (b) Persistent current. 4 Seat No. P.T.O. [4656] – 23 5. a) What is band gap energy ? Explain classification of solids into conductors, semiconductors and insulators on the basis of band theory of solids. 7 b) What are the different methods for synthesis of nanoparticles ? Explain any one method in details. 6 c) A strip of copper of thickness 1.5 × 10–4 m is placed in a magnetic field of 1 T perpendicular to the plane of the strip and a current of 10 A is setup in the strip. What Hall voltage would appear across the width of the strip if concentration of charge carries in copper is 8.5 × 1028 electrons/m3. 4 OR 6. a) Explain the construction and working of solar cell. Explain its IV characteristics. 7 b) Explain any two properties of nanoparticles. 6 c) A germanium sample has 4.56×1022 atoms/cc and a donor impurity in the ratio of one part per 1010 is added to create an N type semiconductor. If the mobility of charge carries is 3900 cm2/ V–s, find the conductivity of silicon. 4 —————— B