1. (a) Define strain.
(b) A rubber band is stretched to twice its original length. Calculate the strain on the rubber band.
2. State three materials used for making optical fibres
3. Name three classes of magnetic materials.
4. (a) What is an intrinsic semiconductor?
(b) Distinguish between the p-type and n-type semi-conductors.
5.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. [g = 10ms ]
6. A black body radiates maximum energy when its surface temperature T and the corresponding wavelengthmax are related by the equation max T = constant. Given the values of the constant and surface temperature as 2.9 x 10 mK and 57°C respectively; Calculate the frequency of the energy radiated.
7. a) What does the acronym LASER stand for?
b) What is a laser?
8. (a) Define uniform acceleration.
(b) Forces act on a car in motion. List the
(i) horizontal forces and their directions;
(ii) vertical forces and their directions
(c) A car starts from rest and accelerate uniformly for 20s to attain a speed of 25 ms. It maintains this speed for 30s before decelerating uniformly to rest. The total time for the journey is 60s.
(i) Sketch a velocity-tune graph for the motion.
(ii) Use the graph to determine the () total distance travelled by the car ( ) deceleration of the car.
The figure here illustrates force-extension graph for a stretched spiral spring. Determine the work done on the spring.