April 2006(For ME)

Sree Narayana Guru College of Engineering and Technology, Payyanur
Second series test - April 2006

ENGINEERING PHYSICS
(For ME)

Time: 2Hours Marks: 50

Part A: Answer all questions

1 State and derive Bragg’s law of X-ray diffraction.
2 What are ultrasonics? How they are detected?
3 Explain the importance of reverberation time in good acoustics.
4 What are semiconductors? Distinguish between p-type and n-type semiconductors.
5 Write a note on BCS theory of superconductivity
(5x4=20 Marks)

Part B: Answer three questions

6 (a) Derive Sabine’s formula for standard time of reverberation. (6 Marks)
(b) Write a note on nondestructive testing by ultrasonic method. (4 Marks)

OR

7 (a) Discuss piezo electric method of producing ultrasonic waves. (6 Marks)
(b) Write a note on radiographic method of nondestructive testing (4 Marks)


8 (a) Describe p-n junction and explain the effect of forward and reverse biasing on the barrier potential of the function. (7 Marks)
(b) The first order spectrum is formed when X-rays of wavelength 1.5Å is incident on a crystal at 12Å. Calculate the interplanar spacing of the crystal (3 Marks)

OR

9 (a) Explain with energy band diagram the classification of solids into metals, semiconductors and insulators (7 Marks)

(b) Find the various possible orders of reflection from a crystal whose lattice constant is 1.4Å. The wavelength of X-ray beam is 1.26Å. (3 Marks)


10 (a) Give an account of various breakdown mechanisms. (5 Marks)
(b) Write a note on Meissner effect. (5 Marks)

OR

11 (a) Write a note on photodiode. (5 Marks)
(b) Distinguish between typeI and typeII superconductors (5 Marks)