1. Compare the colour and efficacy of tungsten-filament, low-pressure sodium-vapour and low-pressure mercury-vapour lamps. 2. What colour of fluorescent lamp should be used for the following: (a) a...

1. Compare the colour and efficacy of tungsten-filament, low-pressure sodium-vapour and low-pressure mercury-vapour lamps. 2. What colour of fluorescent lamp should be used for the following: (a) a butcher’s shop, (b) a restaurant and (c) a jeweller’s? 3.Explain the purpose of the choke in a discharge lighting circuit