Department
of Physics - Dr.Zahir Husain College, Ilyangudi.
Optics
and Spectroscopy –4BPH3C1
Time:
3 Hours Max
Marks: 75
Part –
A (10 x 2 = 20)
Answer All the Questions
- Give
three methods of minimizing spherical aberration.
- Explain briefly about coma
- What
is an air wedge? State its uses.
- State Stoke’s law.
- Distinguish
Fresnel and Fraunhofer Diffraction.
- State Rayleigh criterion for resolution
- What is a quarter wave plate?
- Define
specific rotation or specific rotary power.
- What
is a spectrum?
- Write
note on Stokes lines.
Part – B (5
x 5 = 25)
Answer All the Questions
11. Discuss
the principle of aplanatic lens.
(OR)
Describe how achromatic doublet reduces chromatic
aberration.
- Describe color formation due to thin film interference.
(OR)
Explain the working of Rayleigh interferometer.
13. Explain
Fresnel diffraction light at a circular aperture.
(OR)
Derive an expression for the
resolving power of a grating.
- Discuss Huygens
theory of double refraction at a uniaxial crystal.
(OR)
Give the theory of half wave
plate.
15. Give the theory of origin of
pure rotational spectrum
(OR)
Derive
an expression for the rotational energy of a rigid diatomic molecule.
Part – C (3
x 10 = 30)
Answer any three Questions
- Define angular dispersion and dispersive power. Derive
the conditions to produce (i) deviation without dispersion and (ii) dispersion
without deviation in combination of prisms.
- Explain the working of Michelson Interferometer. How
the wavelength of a monochromatic light can be determined?
- Give the theory of plane transmission grating. Describe
an experiment to determine the wavelength of sodium light.
- Describe Laurent’s half shade polarimeter. Explain how
specific rotary power is determined.
- Discuss the quantum theory of Raman effect.