Chapter Review:

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• The moving air is called the wind.

• Air expands on heating and contracts on cooling.

• Winds carrying water vapour bring rain.

• High-speed winds and air pressure difference can cause cyclones.

• The centre of a cyclone is a calm area. It is called the eye of the storm.

• The instrument that measures the wind speed is called an anemometer.

• As warm air rises, air pressure at that place is reduced and the cooler
  air moves to that place.

Exercise 

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Q1. Fill the missing word in the blank spaces in the following statements:

(a) Wind is——————air.

(b) Winds are generated due to——————heating on the earth.

(c) Near the earth’s surface __________air rises up whereas ___________ air comes down.

(d) Air moves from a region of ——— pressure to a region of——— pressure.

Answer:

(a) Moving (b) Uneven (c) Hot, cool (d) High, low.

Q2. Suggest two methods to find out wind direction at a given place.

Answer:

(i) By watching the direction of movement of a dry leaf released in air.

(ii) By wind watching directuon indicator.

Q3. State two experiences that made you think that air exerts pressure (other than those given in the text).

Answer:

(i) Blowing air in a ballon makes it expand.                            (ii) Blowing air can move curtainon doors and windows. 

Q4. You want to buy a house. Would you like to buy a house having windows but no ventilators? Explain your answer.

Answer:

No. Ventiiars provide a path for warm air to go out of the rooms. Ventilators help in preventing collapase of rooms during high speed winds.

Q5. Explain why holes are made in hanging banners and hoardings.

Answer:

Holes are made in hanging so that blowing and can pass through the holes without damaging them. Otherwise they would be blown away because of air pressure.

Q6. How will you help your neighbours in case cyclone approaches your village/town?

Answer:

(i) By watching everyone about the coming danger.

(ii) Searching for shelter.

(iii) Keeping storage of water and food.

(iv)By setting up first aid facility.

Q7. What planning is required in advance to deal with the situation created by a cyclone?

Answer:

(i) Setting up of a cyclone forecast and warning service.

(ii) construction of cyclone shelters in the cyclone prone areas.

(iii) Making stock of food and water. 

(iv) keeping first aid facility alongwith.

Q8. Which one of the following place is unlikely to be affected by a cyclone.

(i) Chennai   (ii) Mangaluru (Mangalore)  

(iii) Amritsar  (iv) Puri

Answer:

(iii) Amritsar

Q9. Which of the statements given below is correct?

(i) In winter the winds flow from the land to the ocean.

(ii) In summer the winds flow from the land towards the ocean.

(iii) A cyclone is formed by a very high-pressure system with very high-speed winds revolving around it.

(iv) The coastline of India is not vulnerable to cyclones.

Answer:

(i) In winter the winds flow from the land to the ocean.

 

Additional Questions With Solutions

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Ques: What is wind ?
Ans:The moving air is called the wind.

Ques: Which air is lighter? Warm air or cold air.
Ans:Warm air is lighter.

Ques: Why does smoke go up?
Ans: Smoke is warm, by which it is lighter so it goes up.

Ques: How do monsoon winds carry water and its rain?
Ans: Ocean airs are hot and mixed with land air they become hotter which cause rain.

Ques: What is thunderstorm?
Ans: The swift movement of the falling water droplets along with the rising air create lightning and sound. It is this event that we call a thunderstorm.

Ques: What is “Hurricane” or “Typhoon”.
Ans: A cyclone is known by different names in different parts of the world. It is called a ‘hurricane’ in the American continent. In Philippines and Japan it is called a ‘typhoon’.

Ques: What technologies are used to monitor cyclone?
Ans: Monitoring cyclones with the help of advance technology like satellites and radars.

Ques: What is caused cyclone?
Ans: High-speed winds and air pressure difference can cause cyclones.

Ques: Write two properties of wind.
Ans:

1. It always moves.
2. Winds carrying water vapour bring rain.
3. Air moves from the region where the air pressure is high to the region where the pressure is low.

Ques: What are monsoon winds?
Ans: The air over the land gets heated and rises. This causes the winds to flow from the oceans towards the land. These are monsoon winds.

Ques: What factors are responsible for cyclones?
Ans: Factors like wind speed, wind direction, temperature and humidity are responsible for cyclone.

Ques: Suggest two methods to find out wind direction at a given place.
Ans:

1. Seeing the direction of flying a left dry leaf.
2. By wind direction indicator.         

Ques: State two experiences that made you think that air exerts pressure (other than those given in the text).

1. After filling the air the balloon blown.
2. Moving of curtain and door.

Ans: 

 
Ques: You want to buy a house. Would you like to buy a house having windows but no ventilators? Explain your answer.

Ans: No. because the ventilator provide path to excrete hot air from the room. They prevents house by strong wind like storm.  

Ques: Explain why holes are made in hanging banners and hoardings.
Ans: The air puts pressure on the banner but through the holes air passes easily without any damages.

Ques: How will you help your neighbours in case cyclone approaches your Village/town?
Ans:

1. Alerting against the coming dangers
2. Searching for shelter.
3. Keeping storage of water and food.
4. Setting up first aid facility.

Ques: What planning is required in advance to deal with the situation created by a cyclone?
Ans:

1. Setting up cyclone warning system.
2. Setting up food and water storage.
3. Setting up first aid facility. 

Ques: Why are wind currents generated?
Ans: Wind currents are generated due to;

1. Uneven heating between the equator and the poles.
2. Uneven heating of land and water.

Ques: What does monsoon wind carry?
Ans: water

Ques: Where do thunderstorms develop mostly?
Ans: Thunderstorms develop in hot, humid tropical areas like india very frequently.

Additional Questions With Solutions

---

Ques: What is wind ?
Ans:The moving air is called the wind.

Ques: Which air is lighter? Warm air or cold air.
Ans:Warm air is lighter.

Ques: Why does smoke go up?
Ans: Smoke is warm, by which it is lighter so it goes up.

Ques: How do monsoon winds carry water and its rain?
Ans: Ocean airs are hot and mixed with land air they become hotter which cause rain.

Ques: What is thunderstorm?
Ans: The swift movement of the falling water droplets along with the rising air create lightning and sound. It is this event that we call a thunderstorm.

Ques: What is “Hurricane” or “Typhoon”.
Ans: A cyclone is known by different names in different parts of the world. It is called a ‘hurricane’ in the American continent. In Philippines and Japan it is called a ‘typhoon’.

Ques: What technologies are used to monitor cyclone?
Ans: Monitoring cyclones with the help of advance technology like satellites and radars.

Ques: What is caused cyclone?
Ans: High-speed winds and air pressure difference can cause cyclones.

Ques: Write two properties of wind.
Ans:

1. It always moves.
2. Winds carrying water vapour bring rain.
3. Air moves from the region where the air pressure is high to the region where the pressure is low.

Ques: What are monsoon winds?
Ans: The air over the land gets heated and rises. This causes the winds to flow from the oceans towards the land. These are monsoon winds.

Ques: What factors are responsible for cyclones?
Ans: Factors like wind speed, wind direction, temperature and humidity are responsible for cyclone.

Ques: Suggest two methods to find out wind direction at a given place.
Ans:

1. Seeing the direction of flying a left dry leaf.
2. By wind direction indicator.         

Ques: State two experiences that made you think that air exerts pressure (other than those given in the text).

1. After filling the air the balloon blown.
2. Moving of curtain and door.

Ans: 

 
Ques: You want to buy a house. Would you like to buy a house having windows but no ventilators? Explain your answer.

Ans: No. because the ventilator provide path to excrete hot air from the room. They prevents house by strong wind like storm.  

Ques: Explain why holes are made in hanging banners and hoardings.
Ans: The air puts pressure on the banner but through the holes air passes easily without any damages.

Ques: How will you help your neighbours in case cyclone approaches your Village/town?
Ans:

1. Alerting against the coming dangers
2. Searching for shelter.
3. Keeping storage of water and food.
4. Setting up first aid facility.

Ques: What planning is required in advance to deal with the situation created by a cyclone?
Ans:

1. Setting up cyclone warning system.
2. Setting up food and water storage.
3. Setting up first aid facility. 

Ques: Why are wind currents generated?
Ans: Wind currents are generated due to;

1. Uneven heating between the equator and the poles.
2. Uneven heating of land and water.

Ques: What does monsoon wind carry?
Ans: water

Ques: Where do thunderstorms develop mostly?
Ans: Thunderstorms develop in hot, humid tropical areas like india very frequently.