Class 7 Science Question Answers - Wind and Storm

Short  Types Questions

Wind is the movement of air molecules. It is caused by the uneven heating of the Earth's surface by the sun.

Q.2. How does a hot air balloon rise in the air?

A hot air balloon rises in the air because hot air is lighter than cold air. The burner heats the air inside the balloon, making it less dense and causing it to rise.

Q.3. What are seasonal winds and how are they caused?

Seasonal winds are winds that blow in a particular direction during a particular season. They are caused by differences in temperature and pressure between land and water.

Q.4. How is air pressure related to wind?

Air pressure is the force exerted by the weight of the air. Wind is caused by differences in air pressure between two areas.

Q.5. What are cyclones and tornadoes and what are the safety measures to be taken during them?

Cyclones and tornadoes are both types of storms. Cyclones are large-scale weather systems that rotate counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. Tornadoes are small-scale, rapidly rotating columns of air. Safety measures during cyclones and tornadoes include finding a safe shelter, staying away from windows and doors, and staying informed about weather updates. 

Long Types Questions

Wind is caused due to the movement of air from high pressure to low pressure areas. The air moves from a high-pressure area to a low-pressure area to balance the difference. The uneven heating of the earth's surface also contributes to the wind's movement. The sun’s rays heat the earth's surface unevenly, causing air temperature differences. The warm air rises, creating a low-pressure area, while the cold air sinks, creating a high-pressure area. This temperature difference produces wind.

Q.2. Describe the working of a hot air balloon and how it uses the concept of air pressure.

A hot air balloon uses the concept of air pressure to fly. It consists of a large balloon filled with hot air. The air inside the balloon is heated using burners, which makes it less dense than the surrounding air. This causes the balloon to rise up in the air. The hot air balloon moves up as the hot air inside the balloon is lighter than the cold air outside the balloon. The air pressure inside the balloon is lower than the air pressure outside, which creates lift, allowing the balloon to rise.

Q.3. Explain the different types of winds and their characteristics. 

There are mainly two types of winds – local winds and global winds. Local winds are the winds that blow over a small area or region. These winds are caused due to the differences in temperature, pressure, and humidity in the area. Examples of local winds include sea breeze, land breeze, and mountain breeze. Global winds are the winds that blow over large areas, covering the entire earth. These winds are caused due to the earth’s rotation and differences in temperature and pressure. Examples of global winds include trade winds, westerlies, and polar easterlies.

Q.4. Describe the impact of wind and storms on the environment and human life.

Wind and storms have a significant impact on the environment and human life. Strong winds can uproot trees, damage buildings, and cause power outages. Storms, such as hurricanes, cyclones, and tornadoes, can cause extensive damage to property and human life. They can lead to flooding, landslides, and loss of life. Wind energy is a renewable source of energy that can be harnessed to generate electricity. However, it can also have negative impacts on the environment, such as bird and bat fatalities.

Q.5. Discuss the safety measures that should be taken during a cyclone or tornado. 

During a cyclone or tornado, it is essential to take safety measures to protect oneself. Some of the safety measures include staying indoors, away from windows and doors, and taking shelter in a safe room or basement. One should avoid driving or walking through flooded areas or under damaged power lines. It is also necessary to keep a stock of essential supplies, such as food, water, and medicines. One should stay updated with weather alerts and follow the instructions of the local authorities. Evacuation orders should be followed immediately, if issued.