Incandescent lamp, discharge lamp , C.F.L, LED lamp, arc lamp are given for observation .
Answer the following questions after observing them.
The colour of light depends on the gas inside the discharge lamp. Which gases are to be filled for getting white light and yellow light?

Incandescent lamp, discharge lamp , C.F.L, LED lamp, arc lamp are given for observation . Answer the following questions after observing them. Name the lamps which belong to the group of discharge lamp.

Incandescent lamp, discharge lamp , C.F.L, LED lamp, arc lamp are given for observation . Answer the following questions after observing them. Which lamp is used in rescue work during night time and used in search lights ?

Incandescent lamp, discharge lamp , C.F.L, LED lamp, arc lamp are given for observation . Answer the following questions after observing them. Which lamps are harmful to envioronment because of the presence of mercury in it ?

Incandescent lamp, discharge lamp , C.F.L, LED lamp, arc lamp are given for observation . Answer the following questions after observing them. Which metal is used to make filament of an incandescent lamp ? What are the advantages of using this metal as a filament ?

What is the colour of the light emitted by discharge lamp filled with hydrogen when it works ?

What is the colour of the light emitted by discharge lamp filled with nitrogen when it works ?

Two types of lamps are given below . Discharge lamp If nitrogen gas is filled in each lamp,what change will happen to their working ?

Can you now guess why red colour has been given to the tail lamps of vehicles and signal lights ? Discuss and note it down in your science diary .

Discharge lamps are being used widely nowadays. Write down its working by rearranging the following in correct sequence. Ionised atoms collide with unionised atoms , Light energy is emitted when electrons come to initial state for attaining stability. The electrons of unionised atoms go to higher energy levels. The gas in the tube is ionised.