Air around us exerts pressure e
Experiment
Answers
Answer:The envelope of air surrounding the earth is called atmosphere. Air has weight. The weight of air presses our bodies all the time. This weight of air acting on a surface causes air pressure. Air pressure can be understood with the help of certain activities.
Explanation:
Activity I
Materials Required: tumbler, water, square cardboard piece
Method: Fill up the tumbler with water up to the brim. Cover it with cardboard piece and turn the glass upside down. Slowly remove your hand.
Observation: Cardboard does not fall and water stays in the glass.
Inference: air pushes the cardboard up and prevents it from falling.
Activity II
Materials Required: plastic bottle with cap, hot water, cold water
Method: Pour hot water into the plastic bottle. Empty the bottle and put the cap tightly. Pour some ice-cold water on it.
Observation: The bottle will get de-shaped.
Inference: The air from the bottle expands as it becomes hot. When it is cooled, air contracts. The outside air has more pressure and it crushes the bottle.
Some daily life experiences that show that air exerts pressure
You find it easier to row the boat when the wind is blowing behind you.
The wind coming from the back help in flying kite.
When we suck from the straw, the liquid rises in it.
The medicine enters the syringe when a piston is pushed out.
Answer:
We have experienced that when we blow a balloon, the balloon becomes tight. If we try to fill more air, then the balloon will burst after an extent. This happens because air exerts pressure
We have also experienced the movement of fringes of windows and doors of our houses when wind blows in a high speed. This also happens because air exerts pressure