Class 6 science chapter 15 air around us

Please find the attached ppt of Air Around Us

1. Class 6 Science Chapter 15 Air around us Made by Hetanshee

2. How do this firki work ?

3. How do this kite fly?

4. This is all because of Air.

5. You all might have experienced cool breeze during a day.

6. This air balloon also works on simple principle of air.

7. Moving air is also wind. We can find direction of air with help of wind vane.

8. Let us learn some properties of air:-

9. Some properties of air is:- Air is a mixture of substances. Air is colorless, tasteless, odorless and gaseous substance. It occupies space. Air has weight and exerts pressure in all directions. In order to understand various properties, let us try them.

10. Air exerts pressure Aim To show that air exerts pressure. Method 1. Take a glass and fill it only 1/3 of it with water. 2. Cover the mouth of the glass with an index card. 3. Now hold the card in place and invert the class over sink and remove you hand from the card. Conclusion and Observation The card sticks to the glass. This is due to air pressure. The air outside exerts an upward pressure on the index card. The air pressure is more than the weight of the water in the glass.

11. Activity to prove air support burning

12. Lets recall

13. Nitrogen Carbon Dioxide, water vapour , other gases and dust particles 1% Oxygen What is air made up of?

14. Now let us see the properties of each gases

15. Properties of Nitrogen N2 Needed by Plants to make Protein Do not support burning Slightly soluble in water Not essential for breathing

16. Properties of Oxygen O2 Supporter of Combustion Essential for respiration Slightly soluble in water Poor conductor of heat and electricity

17. Properties of Carbon-Dioxide CO2 Neither burns nor supports burning Slightly sour in taste Moderately soluble in water Green plants need CO2 to make food

18. Properties of Smoke Smoke It cause many respiratory diseas e It is always harmful Produced by burning of fuels Consists of fine carbon particles and some gases

19. How is oxygen in the Atmosphere replaced? In chapter 7, We learnt about Photosynethesis . In this process plants make their own food and oxygen is produced along it. Plants inhale carbon-dioxide and exhale oxygen . The balance of oxygen and carbon dioxide in the atmosphere is maintained through respiration in plants, animals and H uman beings. This shows interdependence of plants and animals.

20. LAYERS OF Layers of Atmosphere

21. Windmill A  windmill  is a structure that converts wind power  into  rotational energy  by means of vanes called  sails  or blades. The wind makes windmill rotate. The windmill is used to draw water from tube wells and to run flour mills. Windmills are also used to generate electricity. It is also termed as wind pumps, wind turbines, etc.