1st Class EVS Weather, Air and Water Air

     Air around Us

   

              Air is a natural resource, which we use for breathing.

• It is a mixture of different gases.
• It is found everywhere.
• It cannot be seen with naked eyes.
• It is necessary for life.
• All the living things breathe in air.
• Animals breathe in oxygen and breathe out carbon dioxide.
• Without air, there will be no life on the earth.

 

 

Where does air exist?

(a) Only in our room                                       (b) Only in an empty glass

(c) Everywhere                                                 (d) Only in an empty cup

 

Answer: (c)

Explanation

Option (C) is correct. Therefore, rest of the options is incorrect.

 

 

  What is the colour of air?

(a) Red                                                                 (b) Yellow

(c) Blue                                                                 (d) Colourless

 

Answer: (d)

Explanation

Option (D) is correct because air does not have color. Therefore, rest of the options is incorrect.

    Wind

 

             The moving air is called wind.

• Fast moving wind is called storm.
• Storm may cause some destruction like uprooting of trees, electric poles, and other things.
• Big storms even may destruct the lives of human and animals.
• The slow moving wind is called breeze.
• It is very-very pleasant.
• When wind blows, leaves of plants and trees, our clothes etc shake.

 

 

  What is wind?

(a) Space of the air                                          (b) Volume of the air

(c) Weight of the air                                        (d) Movement of the air

 

Answer: (d)

Explanations

Option (D) is correct. Therefore, rest of the options is incorrect.

 

 

  A light wind does not shake__________.

(a) Leaves                                                           (b) Clothes

(c) Piece of paper                                            (d) Building

 

Answer: (d)

Explanation 

Option (D) is correct because, light wind does not shake building.

Therefore, rest of the options is incorrect.

    Air as a mixture of Gas

 

             Air is a mixture of the following gases:

1. Nitrogen                               
2. Oxygen
3. Carbon dioxide                        
4. Hydrogen
5. Argon                                   
6. Neon
7. Helium

The air present in atmosphere consists of 78 percent nitrogen, 21 percent oxygen and remaining 1 percent is of other gases.

 

 

  Which one of the following is a true statement?

(a) Air is the mixture of solid things

(b) Air is the mixture of liquid things

(c) Air is the mixture of gases

(d) Air is the mixture of food items

 

Answer: (C)

Explanation

Option (C) is correct because, this is a true statement. Therefore, rest of the options is incorrect.

 

 

Which of the following is not a part of air?

(a) Hydrogen                                      

(b) Apple

(c) Nitrogen                                      

(d) Oxygen

 

Answer: (b)

Explanation 

Option (B) is correct because, it is a fruit. Therefore, rest of the options is incorrect.

   Uses of Air

  

          Followings are the uses of air:

• Living things breathe in air to remain live.
• Air is very important for the growth of plants.
• Fresh and cool air is needed for living things to be energetic and agile.
• For making the environment fresh and healthy, natural air is needed.
• Wind is used by man for various purpose, such as, production of electricity.
• In the gas form, air is used in the tyres of vehicles, such as, buses, cars, cycles, motorcycles etc.
• It is also used for filling balloons, footballs, etc.

 

 

  Living things will ____ without air.

(a) Live                                                                

(b) Walk

(c) Talk                                                                 

(d) Die

 

Answer: (d)

Explanation

Option (D) is correct because, living things inhale air to live. Therefore, rest of the options is incorrect.

 

 

  Which one of the following is filled with air?

(a) Table                                             

(b) Balloon

(c) Chair                                                             

(d) Mobile

 

Answer: (b)

Explanation

Option (B) is correct because we use air to fill balloon. Therefore, rest of the options is incorrect.

  Weight of Air

The force, which air is exerting upon us, is called the weight of the air. To understand it we can take the example of a football without air. When we start filling it with air, it gets heavier. Same things happen when the wheels of buses, cars, and cycles are filled with air. Hence we can say that air has weight.

 

 

  Weight of air means _________.

(a) Force                                             

(b) Mass

(c) Energy                                           

(d) All of these

 

Answer: (a)

Explanation 

Option (A) is correct because weight means force exerted. Therefore, rest of the options is incorrect. A balloon is filled with air.

 

 

  A balloon is filled with air. What change will it make to the weight of the balloon?

(a) Decrease                                     

(b) Increase

(c) No change                                

(d) All of these

 

Answer: (b)

Explanation 

Option (B) is correct because air has weight. So it will increase the weight of balloon- Therefore, rest of the options is incorrect.

    Air Occupies Space

We know that air is everywhere. Thus, every living and nonliving things are rapped up in air. We can better understand it with the example of a balloon. When we start filling air in a flat balloon with our mouth, it increases in size.

That means air has occupied the space inside the balloon, thereby increasing its size.

Similarly, air occupies empty space inside a football, wheels of cycles, cars, etc.

Further, air also occupies space in a room, empty glass, empty bowl, etc.

   

 

 

  Which one of the following is filled with air?

(a) Solid sphere                                               

(b) Empty basket

(c) A solid iron rod                                          

(d) A tree stem

 

Answer: (b)

Explanation

Option (B) is correct, because we know that air occupies ail the empty space. Therefore, rest of the options is incorrect.

 

 

A balloon increases in size, because _______ inside it.

(a) Air is filled into it                                      

(b) Water is filled into it

(c) Fire filled into it                                       

(d) Anger filled into it

 

Answer: (a)

Explanation

Option (A) is correct, because air occupies empty space inside a balloon, thereby increasing its size. Therefore, rest of the options is incorrect.

 

• We breathe about two gallons of air every minutes.
• Oxygen is the most abundant element in air, water and land.

 

• Air is essential for all living organisms.
• Living things will die without air.
• Air is invisible and has no definite shape.
• Air exits everywhere and every living and non-living things are wrapped in it.
• The treasure of air never ends.
• Wind is the movement of air.
• The fast moving air is called storm.
• Slow and smooth moving air is called breeze.
• Air is a mixture of gases.
• Plants need fresh and cool air to grow.
• Air occupies space all around.