Shanmugha Arts Science Technology and Research Academy (SASTRA) University 2009 B.Tech Electronics and Communications Engineering ENGINEERING PHYSICS (I-term ) - Question Paper

Subject name ENGINEERING PHYSICS-I
examination TYPE I-MID SEMESTER
PART-A
ans all the ques.. 10X2=20M
01. Explain Optical Pumping.
02. Prove that LAER action is not possible in Optical frequencies.
03. What are Metastable states?
04. What is the use of Nitrogen and Helium in CO2 LASER.
05. Classify various kinds of LASERs with examples.
06. What is meant by LIDAR? What is its use?
07. For InP LASER diode , the wavelength of light emitted is 1.55X(10)-6M. What is its band gap in eV?
08. An Optical fiber core and its cladding have refractive indexes of 1.545 and 1.495 respectively. compute its Critical Angle and Acceptance Angle.
09. The refractive index of core and cladding of an Optical fiber are 1.54 and 1.5 respectively. compute the Numerical Aperture of the Optical fiber.
10. Differentiate ranging from Extrinsic Fiber Optic sensor and Instrinsic Fiber Optic sensor.

PART-B
ans any 3 ques.. 3x10=30M
11. Discuss Einstein’s Quantum theory of Radiation & Derive Einstein’s coefficients.
12. Explain in detail the construction and working of semiconductor Diode LASER with neat diagram.
13. • Differentiate ranging from Holography and Photography.
• How 3D profiling is utilized in manufacturing of engineering components?
14. • Derive an expression for Numerical Aperture and acceptance angle.
• Discuss different methods of sensing pressure using Fiber Optic sensor.

Earning:   Approval pending.