B B1902

Reg No.: Name:

APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
FIRST SEMESTER B.TECH DEGREE EXAMINATION, DECEMBER 2018

Course Code: PH100 .
Course Name: ENGINEERING PHYSICS
Max. Marks: 100 Duration: 3 Hours
PART A
Answer all questions, each carries 2 marks. Marks

1 What do you understand by Quality factor? On what factors does it depend? (2)

2 Write down equation that represents a wave having amplitude 5cm, period (2)
0.002 sec and velocity 1500m/s that moves along —x axis.

3 Why is the centre of Newton’s rings pattern dark in reflected system? (2)

4 What do you mean by resolving power of an optical instrument? (2)

5 Define Plane of Vibration and Plane of Polarization. (2)

6 Why a superconductor is called a perfect diamagnet? (2)

7 What are the characteristics of a well-defined wave function? (2)

8 Find the smallest volume of a unit cell in phase space for a particle obeying (2)
quantum statistics.

9 What is absorption coefficient? (2)

10 What is SONAR? Give one use of it. (2)

11 Distinguish between spontaneous emission and stimulated emission. (2)

12 What is a photo-detector? Give two examples. (2)

PART 8
Answer any 10 questions, each carries 4 marks.

13 What is the condition for critical damping in the case of a damped harmonic (4)
oscillator? With the help of the expression for displacement write how this
condition affects the amplitude of the oscillator?

14 The string of violin 36 cm long and has a mass of 0.2gm. With what tension (4)
must be stretched to tune 1000 Hz.

15 In a Newton’s ring arrangement, if a drop of water (u = 4/3) is placed in (4)
between lens and the plate, the diameter of the 10" dark ring is found to be 0.6
cm. Obtain the radius of curvature of the face of the lens in contact with the
plate. The wavelength of light used is 6000A.

16 Compare grating and prism spectra. (4)

17 A plane polarised light is incident on a piece of quartz and parallel to the axis. (4)

Find the least thickness for which the ordinary and extra-ordinary rays combine
to form plane polarized light. Given that the refractive indices for the ordinary
and extra-ordinary rays are 1.5442 and 1.5533 respectively and wavelength of

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