problem 1: What are the various dielectric materials according to their physical nature?
problem 2: Describe about surge voltages their distribution and control?
problem 3: Describe in brief the different numerical methods available for estimation of electrical field distribution in dielectric media?
problem 4: Discuss in brief about charge simulation method for solving field problems and estimation potential distribution.
problem 5: Describe the relative benefits and drawbacks of different numerical methods for solution of field problems?
problem 6:
a) Obtain the number of collision/second and the average time between two collisions, if the average velocity of the gas in the gap is 500m/s and mean free path is 107 m.
b) Derive the expression for collision cross-section in terms of mean free path.
problem 7: Describe in detail about thermal breakdown method in commercial liquids.
problem 8:
a) Describe short term and long term breakdown mechanisms which occur in a composite solid dielectrics.
b) Describe in brief about various solid dielectrics used in practice.
problem 9: prepare brief notes on:
a) Photo-ionization.
b) Secondary ionization.
problem 10: Define Townsend's first and second ionization coefficients. Describe the Townsend's criterion for a spark breakdown.
problem 11: Describe about Paschan’s Law of break down in gases?