NRI INSTITUTE OF TECHNOLOGY I MID EXAM QUESTIONS ENGINEERING PHYSICS UNIT-I 1. What are the conditions to obtain the maximum and minimum intensities in The reflected light due to thin film. 2. a)Derive the expression for resolving power of grating. b) Explain the theory of plane diffraction grating. 3. Discuss Fraunhofer diffraction due to double slit and draw the intensity distribution curve. 4. a) What is meant by double refraction? b) What are quarter wave and half wave plates? Derive an expression for their thickness. 5. Discuss the theory of Newton’s rings with relevant diagram. UNIT-II 1. Derive the relation between the probabilities of spontaneous and stimulated emissions in terms of Einstein coefficients. 2. a) What is the principle behind the functioning of an optical fiber? b) Calculate the numerical aperture and acceptance angle for an optical fiber with core and cladding refractive indices being 1.48 and 1.45 respectively. 3. Explain the construction and working of ruby laser. 4.a) State and explain Bragg's law of x-ray diffraction. b) What are miller indices? What are their important features? 5. Explain the types of crystal systems and Bravais lattices. UNIT-III 1. a) Show that D = €0E+P. b) Derive clausius - mossotti relation in dielectrics. 2. Explain the classification of magnetic materials. 3. Explain the origin of different types of polarization 4. a) what is Meissner effect? Explain. b) Explain type-I & type-II superconductors 5. Explain hysteresis loop observed in ferro magnetic materials. .