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A192003 Pages:2

1.544 and 1.553 respectively.
Explain Type I and Type II Superconductors.

With the help of uncertainty principle, explain why electron cannot exist
inside the nucleus.

Prove that at absolute zero, the probability of occupancy of an energy level
below Fermi level is 1. Also show that under the same conditions the
probability of occupancy of an energy level above Fermi level is 0.

A hall has a volume of is 600 ന. It is required to have the reverberation
time of 1.5s. What should be the total absorption in the hall?

A nickel rod of length 10 cm is used in a magnetostriction oscillator.
Calculate the frequency of ultrasonic waves generated, Nickel has Young’s
modulus of 210 © Pa and density of 8900 kg/m°.

Distinguish between spontaneous and stimulated emission of radiation.

A fibre cable has an acceptance angle of 30° and a core of refractive index
1.4. Calculate the refractive index of the cladding.
PART ^
Answer any three questions, each carries 6 marks.

Considering transverse vibrations of a stretched string derive the one
dimensional wave equation.
Show that the radius for 75 dark ring formed in a Newton’s rings
experiment is proportional to ஷி.
Describe the construction of a Nicol prism. Explain its working as a
polarizer and as an analyzer.
Compare the Maxwell-Boltzmann, Bose-Einstein and Fermi-Dirac
Statistics.
PART D
Answer any three questions, each carries 6 marks.

Define reverberation and reverberation time. What is the significance of
reverberation time? Compare reverberation and echo.

What is magnetostriction effect? With the help of a circuit diagram explain
the production of ultrasonic waves using a magnetostriction oscillator.
What are the basic components of a laser system? How are these
requirements satisfied in the case of Ruby laser?

What is Photovoltaic effect? Explain the structure and working of a solar
cell. Draw the I-V graph.

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