Download DBATU B-Tech 1st Year 2017 May Engineering Physics Question Paper

Download DBATU (Dr. Babasaheb Ambedkar Technological University) B.Tech First Year 2017 May Engineering Physics Question Paper

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DR. BABASAHEB AMBEDKAR TECHNOLOGICAL UNIVERSITY, LONERE
First Year B. Tech. (Mechanical, Chemical Civil and Petrochemical)
' End Semester Examination 4017.
Subject: Engineering Physics
3hour 2 9 APR 2017 Maximum Marks: 60
Instructions to the students:
I . All questions are compulsory and each question carries 10 marks
2. Illustrate your answers with neat sketches. diagrams etc. wherever necessary.
3. Necessary data is given in the respective questions. if such data is not given, it means that the know|cdge of
the pan is part of examination.
4. If some part or parameter is noticed to be missing, you may appropriately assume it and should mention it
clearly
Q.l Attempt the following.
3) Obtain the differential equation of damped oscillation and ?nd its general solution. 7
b) Calculate the natural frequency ofthe ultrasonic waves generated by a quartz crystal having
thickness of5.5 mm.
Given Y: 30 GPa, p = 2650 kg/m3 3
0.2 Attempt the following
a) Explain theory of Newton?s rings for re?ected light. 7
b) Light of wavelength 5500 A falls normally on a thin wedge shaped ?lm of R.I. 1.4 forming
fringes that are 2.5 mm apart. Find the angle of wedge. 3
OR
Q.2 Attempt the following
a) Explain the principle and working of He-Ne gas laser 7
b) The numerical aperture of an optical ?ber is 0.5 and Core refractive index is 1.54. Find the
refractive index of the cladding. 3
0.3 Attempt the following. -
3) Explain the principle and working of Bainbridge mass spectrograph. 7
b) What is Uncertainty principle? Using this principle prove that electron cannot exist in the
nucleus. 3

Q.4 Attempt the following.
a) State and prove Mosley?s law. What is its importance? 7
b) Silver has FCC structure and its atomic radius is 1.414 A. Find the interplaner spacing for ?
(200) planes. 3
0.5 Attempt the following.
' a) What is Hysteresis Curve? Explain retentivity, coercivity. Explain B-H curve on the basis of
domain theory. 4
b) What is Meissner effect and effect of external magnetic ?eld on superconducting state of
material? 6
At 6 K, critical ?eld is 5 x 103 NHL Calculate transition temperature when critical ?eld is 2 x
10? A/m at 0 K.
Q.6 Attempt any two of the following.
a) What is Hall effect? Derive an expression for Hall Coef?cient and mobility of charge
carriers. 5
b) What is electric polarization? Explain with diagrams different types of polarizations in
dielectric 5
c) Derive an expression for electromagnetic wave in free space. Find the value of velocity of
light in free space. 5