1)(a) Describe the method of working of Neon lamp with a suitable and neat sketch.
(b) Define the Lambert’s cosine law of illumination.
2) Evaluate the number and wattage of lamps that would be required to illuminate ever shop space 60 X 15metres, by means of lamps mounted 5metres above working plane. Average illumination required is about 100 Flux, Co-efficient of utilization =0.4, luminous efficiency is 16 lumens per Watt. Suppose a space height ratio of unity candle power depreciation of 20%.
3)(a) Two lamps one 200cp and another 500cp are hung at the height of 10metres and 25metres respectively. Horizontal distance between poles is 80metres. Find out the illumination at the midpoint between poles on the ground.
(b) Write down the requirements of good heating materials.
4)(a) Describe the working of sodium vapour lamp with in a neat sketch.
(b) what do you mean by Halogen lamp?
5) Describe the operation principle and working of mercury vapour lamp and compare its performance with the fluorescent lamp. Explain with a neat sketch the principle of operation of a fluorescent lamp. Write down the function of each component.
6) Describe the types of lamps and lighting fitments you must choose for:
(i) A large machine shop with rows of drilling machines
(ii) A drawing office and lathes.
7)(a) A 100 candle power lamp is hung 2m above centre of circular area of 3 diameters. Find out the illumination at (i) the centre of the area, (ii) a point on the circumference of the area, (iii) average illumination. Determine also the average illumination, if a reflector of 50% efficiency is used.
(b) Lamp of 300 candle power is placed 1.5 m below a reflecting plane mirror surface, that reflects 70% of the light falling on it. Determine the illumination at a point 4m.