This document discusses different electric sources of light, including incandescent lamps, discharge lamps, fluorescent lamps, and compact fluorescent lamps. It describes the key parts and properties of each type of lamp. Incandescent lamps contain a thin tungsten filament, glass bulb, and connecting metal. Tungsten is used for its high melting point and ability to remain white hot. Discharge lamps contain a gas-filled glass tube and electrodes that produce light in different colors depending on the gas. Fluorescent lamps contain a heating coil, mercury vapor, fluorescent substance, and glass tube. Compact fluorescent lamps contain an electronic circuit and fluorescent tube to provide energy savings over incandescent lamps.

2. KERALA UNIVERSITY
COLLEGEOF TEACHER
EDUCATION,ANCHAL
Presented By
Name : Anusree V S
Optional : Physical Science
Reg No : 13975008

3. ELECTRIC SOURCE OF
LIGHT
1. INCANDESCNET LAMP
2. DISCHARGE LAMP
3. FLUORESCENT LAMP
4. COMPACT FLUORESCENT LAMP
5. LIGHT EMITTING DIODE ( LED )

5. PARTS
1.A THIN TUNGSTEN FILAMENT
2.GLASS BULB
3.METAL PART WHICH CONNECTS
THE HOLDER PIN

6. 1. INCANDESCENT MEANS GLOWING ON BEING HEATED.
2. TUNGSTEN IS THE MATERIAL USED FOR MAKING FILAMENT OF AN
INCANDESCNET LAMP.
PROPERTIES OF TUNGSTEN
1. HIGH MELTING POINT.
2. HIGH DUCTILITY.
3. ABILITY TO REMAIN WHITE HOT FOR LONG TIME.
4. HIGH RESISTIVITY.
5. HIGH RESISTANCE.

7. DISCHARGE
LAMP

8. PARTS
1. A GLASS TUBE FILLED WITH SUITABLE GAS AT LOW PRESSURE
2. ELECTRODES AT BOTH ENDS.
SL NO GAS IN THE DISCHARGE
TUBE
COLOUR OF
LIGHT
1 NEON ORANGE, RED
2 NITROGEN RED
3 SODIUM VAPOUR WHITE
4 CHLORINE GREEN
5 MERCURY VAPOUR WHITE
6 HYDROGEN BLUE

9. FLUORESCENT LAMP
LAMP

10. PARTS
1.HEATING COIL COATED WITH THORIUM OXIDE
2.GAS OF ARGON AND MERCURY VAPOUR.
3.FLUORESCENT SUBSTANCE.
4.GLASS TUBE

11. ADVANTAGES OF FLUORESCENT LAMP OVER
INCANDESCENT LAMP
1. SAVES ELECTRICAL ENERGY TO A GREAT EXTENT.
2. THE INCONVENIENCE CAUSED BY SHADOW IS MINIMISED.
3. GIVES GREATER INTENSTIY OF LIGHT.
4. ENERGY LOSS IS LESS.
5. LIFE SPAN OF FLUORESCENT LAMP IS 5 TIMES THAT OF INCANDESCENT LAMP.

12. COMPACT
FLUORESCENT
LAMP

13. 1. A CFL HAS AN UNIT OF ELECTRONIC CIRCUIT AND A
FLUORESCENT TUBE CONTAINING MERCURY VAPOUR.
MERITS OF CFL
1. A VERY LOW POWER IS ENOUGH.
2. LIFE OF CFL IS 5 TIMES THAT OF THE INCANDESCENT LAMP
3. GIVES MORE LIGHT
4. MAJORITY OF ENERGY USED IS CONVERTED INTO LIGHT
ENERGY