Weather is the state of the atmosphere at a particular place and time as regards heat, cloudiness, dryness, sunshine, cold, wind, rain, etc. The weather of a place can change very quickly. If yesterday was cold, today it may be very hot and sunny. If today the weather is sunny with a clear sky, tomorrow there might be clouds and rain. Thus, we used to describe weather as sunny, cloudy, rainy and snowy.
A. ANSWER THESE QUESTIONS.
What is the difference between weather and climate?
Weather at a given place and time is its atmospheric conditions like hot, cold or windy. The weather of a place can change quickly withing a few days or even on the same day.
Climate is the kind of weather a place has over a long period of time. Unlike the weather, the climate of a place remains the same for many years.
How are clouds formed? How do we get rain from these clouds?
The sun’s heat changes water from the rivers and lakes to water vapour. The water vapour rises into the sky with warm air. As it rises higher, the warm air cools down. The water vapour in it changes back to tiny drops of water which floats in the air. The large number of these floating drops of water form cloud.
Several water drops may join together to form bigger drops. These are too heavy to float, so they fall down to the earth as rain.
What are the four main steps of the water cycle.
The four main steps of the water cycle are-
1. Water changes to water vapour and rises upward.
2. As it rises higher, the water vapour changes back to tiny drops of water to form cloud.
3. The bigger drops of water are too heavy to float so they fall down to the earth as rain.
4. Some of the rain water that falls on the earth seeps into the ground. The rest of it goes back to the lakes, rivers and oceans.
How do we get hail?
Sometimes raindrops are carried upward by rising air to very cold regions where they freeze. A number of frozen drops join to form balls of ice which is called hail.
List two points on which the climate of a place depends.
1. How far the place is from the equator. Places near the equator get direct rays of the sun and have a hot climate.
2. How high the place is. The air gets colder as we move up. Places in hills and mountains have a cooler climate.
What kind of climate does India have?
India is closer to the equator then to the poles. So, India have a warm climate. But places in India that are in high mountains have a cold climate.
Why do clothes take longer to dry on a humid day?
When there is lot of water vapour in the air we say it is humid. On a humid day the air cannot take up any more water vapour, so wet clothes take longer to dry.
What is dew?
Colder air is less able to hold water vapor than warm air. This forces water vapor in the air to convert into drops of water. These drops of water are called dew.
Define humidity?
The amount of water vapour in the air is called humidity.
B. TRUE OR FALSE.
Clouds are made of small drops of water or crystals of ice.
Frozen dew is called frost.
We feel sticky and uncomfortable on a humid day.
We get hail, or frozen rain, in cold weather.
It cannot snow on high mountains near the equator.
Gale is a strong wind.
The climate can change quickly, but the weather does not change for many years.
Places near the poles have hot climate.
The small drops of water that form on leaves and grass at night are called fog.
Bad weather with strong winds and rain is called storm.
1. True
2. True
3. True
4. True
5. False
6. True
7. False. Climate of a place remains the same for many years.
8. False. Places near the poles have cold climate.
9. False. The small drops of water that form on leaves and grass at night are called dew.
10. True
