This PSEB 7th Class Science Notes Chapter 8 Winds, Storms and Cyclones will help you in revision during exams.
PSEB 7th Class Science Notes Chapter 8 Winds, Storms and Cyclones
→ The air around us exerts pressure.
→ Moving air is called wind.
→ Very strong wind lowers the pressure.
→ Air expands on heating and contracts on cooling.
→ Hot air is lighter than cold air.
→ The wind moves from high-pressure areas to low-pressure areas.
→ Wind speed is measured with an Anemometer.
→ The direction of wind speed is measured by the wind vane.
→ Wind currents (movement) are caused by the uneven heating of the earth.
→ Monsoon winds are filled with moisture (water vapours) and bring rain.
→ Cyclones are destructive.
→ A cyclone crossed the coast of Orissa on October 18, 1999.
→ Cyclones have higher wind speeds.
→ A cyclone is a very strong whirlwind that revolves around very low-pressure areas.
→ A hurricane is a storm with strong winds blowing through, in a funnel-shaped cloud.
→ The loud noise produced during lightning is called thunder.
→ Heavy rain with strong winds is called a storm.
→ Hurricanes in the United States and typhoons in Japan are cyclones.
→ Tornadoes are dark cone-like clouds that form between the earth’s crust and the sky.
→ All kinds of natural disasters like cyclones, tornadoes, etc. destroy trees, wires, and communication systems.
→ Special policies are adopted during disasters.
→ A cyclone warning is given 48 hours in advance with the help of satellite and radar.
→ And self-help is the best help. So it would be helpful to plan your safety in advance and take precautionary measures before any cyclone actually strikes.
→ Wind: Fast-moving air is called wind.
→ Monsoon winds: The winds that come from the sea and carry water are called monsoon winds.
→ Tornado: Dark coloured cone-like clouds whose cone structure is from sky to earth is called Tornado.
→ Cyclone: A violent wind that moves in a circle causing a storm is called a cyclone.