B 0000PHT110121905 Pages: 3

Reg No.: Name:
APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY

B.Tech 51 (Special Improvement) Examinations January 2021 (2019 scheme)

Course Code: PHT 110
Course Name: ENGINEERING PHYSICS B
(2019-Scheme)

Max. Marks: 100 Duration: 3 Hours
PARTA
Answer all questions, each carries 3 marks. Marks
1 Draw the displacement — time curves for all types of damped harmonic )3(

oscillators and write the conditions.
2 List two differences between longitudinal and transverse waves. Give an (3)

example for each.

3 Explain colours of thin films. (3)
4 What is Rayleigh’s criterion of spectral resolution? (3)
5 State and explain Heisenberg’s uncertainty principle. (3)
6 What is the significance of surface to volume ratio in nanomaterials? (3)
7 What is echelon effect? How it can be resolved? (3)
8 What is magnetostriction effect? Give two examples for magnetostrictive (3)
materials.
9 Give any three properties of laser. (3)
10 Write a short note on intensity modulated sensor. (3)
PART B
Answer one full question from each module, each question carries 14 marks
Module-I

11 a) Formulate the differential equation of a forced harmonic motion. Find the (10)
expressions for its amplitude and phase.
b) A damped oscillator of mass 2g has a force constant 10 N/m and damping (4)
constant2 51, Find the angular frequency with and without damping.
12 a) What is a one dimensional wave and derive the one dimensional wave (10)
equation. Define wavelength, time period, frequency and wave velocity. Also
obtain expressions for them.

b) A string of mass 0.65 kg is stretched between two supports 30 m apart. If the (4)

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