long-questions-ch-18-p12

S.No	Questions
Question 1	State Einstein’s postulates of Special Theory of Relativity. Discuss its results. See Answer
Question 2	What are the main features of the thermal radiations from a black body? Discuss Planck’s quantum theory and its importance in Physics. See Answer
Question 3	What are the main features of photoelectric effect? Discuss the failure of classical Physics and success of photon concept in explaining the effect. See Answer
Question 4	What is Compton Effect? Develop a mathematical relation for the Compton shift. See Answer
Question 5	Write note on pair production and annihilation of matter. See Answer
Question 6	What is de’ Broglie’s hypothesis? Describe an experiment to show that particle has wave characteristics. See Answer
Question 7	What is meant by wave-particle duality? Explain. See Answer
Question 8	State and explain Hysenberg’s uncertainty principle. Justify the validity of this principle by a thought experiment. See Answer

Numerical Problems included in the theory.

Problem	The rest mass of an electron is 9.11 × 10^-31 kg. Calculate the corresponding rest energy. See Answer
Problem	A space ship is measured 100 m long while it is at rest with respect to an observer of this ship now flies by the observer with a speed of 0.99c. What length will the observer find for the spaceship? See Answer
Problem	A traveler on a train with a speed of 0.8c, picks up and open a newspaper. The event takes 1.0 s as measured by the train traveler. What would be the time observed by the person standing by the side of the track? See Solution
Problem	Superman, who has an exceptionally strong arm, throws a fast ball with a speed of 0.9 c. If the rest mass of the ball is 0.5 kg, what is its mass in flight? See Solution
Problem	The temperature of the skin is approximately 35 deg C. What is the wavelength at which the peak occurs in the radiation emitted from the skin? See Solution