Physics Past Questions and Answers

Name three classes of magnetic materials.

(a) What is an intrinsic semiconductor?
(b) Distinguish between the p-type and n-type semi-conductors.

A missile is projected so as to attain its maximum range. Calculate the maximum height attained if the initial velocity of projection is 200 ms\(^{-1}\). [g = 10ms\(^{-2}\)]

A black body radiates maximum energy when its surface temperature T and the corresponding wavelength \(\lambda\)max are related by the equation \(\lambda\)max T = constant. Given the values of the constant and surface temperature as 2.9 x 10\(^{-3}\) mK and 57°C respectively; Calculate the frequency of the energy radiated.

a) What does the acronym LASER stand for?
b) What is a laser?