(a) Define strain.

(b) A rubber band is stretched to twice its original length. Calculate the strain on the rubber band.

State three materials used for making optical fibres.

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\(^{-2}\)]