Define the terms critical potential, excitation potential and ionization potential. Describe Frank-Hertz experiment for determining the critical potentials. Show how the results of the experiment confirm Bohr’s postulates.

What are the postulates of wave mechanics? Derive Schrodinger wave equation. Discuss significance of the wave function.

Explain potential energy barriers for the charge carriers in BJT. Describe how the transistor works as a voltage amplifier.

Develop differential equation for the oscillation of a mass-spring system and write its solution.

Discuss the electrical conductivity of a semiconductor.

Explain Bloch theorem for a particle moving in a periodic potential.

suppose a body of an ice skater has a moment of inertia 4 kgm² and her arms have a mass 5 kg each with center of mass at 0.4 m from her body. she started to turn at 0.5 rev/sec on the point of her skete with her arms out stretched . She then pulled her arms inward so centered of mass is at axis of her body is zero. What is the speed of rotation?

An electron is placed midway between two fixed charges, q1= 2.5 X 10-10 C and q2 = 5 X 10- 10 C. If the charges are 1 m apart, what is the velocity of the electron when it reaches a point 10 cm from q2?

The uncertainty in the position of a particle is equal to the size of the de Broglie wavelength of the particle. Calculate the uncertainty in the velocity of the particle in terms of the velocity of the de Broglie wave associated with the particle.

Suppose that the effective mass of holes in a material is four times that of electrons. At what temperature would the Fermi level be shifted by \(10\%\) from the middle of the forbidden energy gap? Consider \(E_g = 1\,\text{eV}\).

Find the truth table for the circuit shown in the given figure. What logic function does the circuit perform?