Table of contents | |
Section A: Multiple Choice Questions | |
Section B: Short Answer Questions | |
Section C: Fill in the Blanks | |
Section D: Match the Column | |
Section E: True or False |
Correct Answer is Option (a)
The main cause of wind is the unequal heating of the Earth's surface by the sun. This creates differences in air temperature and pressure, which results in the movement of air or wind.
Q.2. What are the hot air balloons filled with?
(a) Water
(b) Helium
(c) Hydrogen
(d) Hot air
Correct Answer is Option (d)
Hot air balloons are filled with hot air using a burner that heats the air inside the balloon. As hot air is lighter than cold air, the balloon rises and floats in the sky.
Q.3. What are the seasonal winds called that blow over the Indian subcontinent?
(a) Monsoons
(b) Typhoons
(c) Hurricanes
(d) Tornadoes
Correct Answer is Option (a)
The seasonal winds that blow over the Indian subcontinent are called monsoons. They bring heavy rainfall in different parts of India and are essential for agriculture.
Q.4. What is the unit used to measure air pressure?
(a) Kilometer
(b) Barometer
(c) Thermometer
(d) Hygrometer
Correct Answer is Option (b)
Air pressure is measured using a device called a barometer. It measures the weight of air above a particular area and is usually measured in millibars or inches of mercury.
Q.5. Which type of wind is formed due to the difference in air pressure over a small area?
(a) Local winds
(b) Global winds
(c) Seasonal winds
(d) Cyclonic winds
Correct Answer is Option (a)
Local winds are formed due to the difference in air pressure over a small area. They are usually short-lived and affect only a small region. Examples include sea breezes, land breezes, and mountain winds.
Air pressure is the weight of the atmosphere pressing down on the Earth's surface. It is caused by the weight of the air molecules in the atmosphere and is affected by temperature, humidity, and altitude. Air pressure decreases with altitude and is measured using a barometer.
Q.2. How does moving air create lift?
Moving air creates lift by exerting a force on an object in the opposite direction of the wind. This is known as Bernoulli's principle and is based on the fact that air moving faster over a curved surface creates a lower pressure than air moving slower over a flat surface. This difference in pressure creates a lift force that can be used to lift objects such as airplanes and kites.
Q.3. Name three types of winds and describe their characteristics.
The three types of winds are local winds, global winds, and seasonal winds. Local winds are formed due to the difference in air pressure over a small area and are usually short-lived. Global winds are caused by the rotation of the Earth and are long-lasting. Seasonal winds are caused by differences in temperature and pressure between different regions and are typically associated with specific seasons. Examples of each type of wind include sea breezes, trade winds, and monsoons.
Q.4. What are the effects of a cyclonic storm?
Cyclonic storms can have a devastating impact on human lives and the environment. They can cause flooding, landslides, and damage to infrastructure such as buildings and roads. Cyclones can also disrupt the economy by disrupting transportation and communication networks. In extreme cases, they can cause loss of life and property damage on a large scale.
Q.5. What are the safety measures to be taken during a cyclone?
During a cyclone, it is important to take safety measures to protect yourself and your family. These include staying indoors and away from windows, keeping a stock of food and water, and having a first aid kit on hand. It is also important to monitor weather reports and follow the instructions of local authorities.
Wind is caused due to the difference in air pressure.
Wind is the movement of air from high pressure to low pressure. The greater the difference in pressure, the stronger the wind.
Q.2. ________ is a device used to measure wind speed.
Anemometer is a device used to measure wind speed.
Anemometer is a device that measures wind speed and direction. It is commonly used in weather stations and airports.
Q.3. Hot air balloons rise up as hot air is __________ than cool air.
Hot air balloons rise up as hot air is less dense than cool air.
Hot air balloons rise up because hot air is lighter than cool air. When the air inside the balloon is heated, it becomes less dense and rises up, carrying the balloon with it.
Q.4. The wind that blows in a particular direction during a particular season is known as __________ wind.
The wind that blows in a particular direction during a particular season is known as seasonal wind.
Seasonal winds are also known as monsoons. They are caused by the differential heating of land and sea during different seasons, which creates a pressure gradient and results in winds blowing in a particular direction.
Q.5. The circulation of air in the atmosphere is due to the difference in __________.
The circulation of air in the atmosphere is due to the difference in temperature and pressure.
The circulation of air in the atmosphere is driven by the difference in temperature and pressure. Warm air rises and cool air sinks, creating a vertical circulation, while the pressure gradients created by this movement result in horizontal circulation patterns.
1. Air Pressure - Cyclonic Storm
Cyclonic storms are caused due to low air pressure. The lower the air pressure, the stronger the storm.
2. Hot Air Balloons - Rising Warm Air
Hot air balloons work on the principle of rising warm air. As the air inside the balloon is heated, it becomes less dense and rises up, lifting the balloon.
3. Seasonal Winds - Moving Air and Lift
Seasonal winds are caused due to the movement of air from high pressure to low pressure areas. This movement of air creates lift and affects the direction and speed of the wind.
4. Effects of Storms - Safety Measures during a Cyclone
Storms can have various effects such as heavy rainfall, strong winds, lightning, and flooding. During a cyclone, it is important to take safety measures such as staying indoors, keeping emergency supplies, and following evacuation orders.
5. Impact of Wind - Wind Energy
Wind energy is a renewable energy source that is generated by harnessing the power of wind. The impact of wind can be used to generate electricity through wind turbines.
True.
Wind is caused due to the difference in air pressure. Air moves from high-pressure areas to low-pressure areas, creating wind.
Q.2. Hot air balloons rise up as hot air is lighter than cool air.
True.
Hot air is lighter than cool air, so it rises up in the atmosphere. The hot air inside the balloon makes it rise up.
Q.3. Monsoon winds blow from the land towards the sea.
False.
Monsoon winds blow from the sea towards the land. During summer, the land gets heated up more than the sea, which causes the air to rise and draw in moist air from the sea, leading to monsoon rains.
Q.4. Anemometer is used to measure the temperature of the wind.
False.
Anemometer is used to measure the speed of the wind, not the temperature.
Q.5. Cyclones and Tornadoes are the same.
False.
Cyclones and Tornadoes are not the same. Cyclones are large systems of low-pressure areas with strong winds and rain, while Tornadoes are small, rotating columns of air that can cause severe damage.
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