Chapter: 10. Sun As A Natural Resource
Let’s Begin
Imagine a day when the Sun does not rise. List any five things that would not happen on that day. (Hint: Think of how we, and other living things, depend on the Sun for their daily activities. Also think how water cycle would be affected.) Plants would not be able to make food (photosynthesis). There would be no daylight, only darkness. The Earth would become extremely cold. The water cycle would be affected, leading to no evaporation and thus no rain. People and animals would not be able to carry out many daily activities that depend on light and warmth. Think!
Name two fruits you like to eat in: Name two clothes you prefer wearing in: Quick check 1
Write R for renewable energy and NR for non-renewable energy.
Water droplet (hydro-power): R Fuel pump (petrol/diesel): NR Think!
Have a class discussion on which of the following bulbs is more energy-efficient—LED or fluorescent? LED bulbs are generally more energy-efficient than fluorescent bulbs. Quick check 2 - Fill in the blanks.
a. A solar geyser is used to heat (juice/water). b. (Spring/Autumn) season has beautiful flowers. c. (Solar cells/Bulbs) are devices that convert light energy directly into electrical energy. d. We prefer (dark/light) -coloured clothes on a hot sunny day. e. The word ‘solar’ means related to the (Sun/Moon). Run-Through
I. Very Short Answer Questions
A. State True or False.
Solar cells convert electrical energy into light energy. The Sun does not affect the weather. The Sun’s rays are slanting in the afternoon. There are five major seasons in India. B. Match the following.
Summer - e. Hot and thirsty Monsoon - d. Cloudy and rainy Autumn - a. Trees shed leaves Spring - c. Beautiful flowers C. Unjumble the letters and define the following words.
SUNRISE: The time in the morning when the Sun appears above the horizon. RENEWABLE: Sources of energy that will not run out and will continue to provide us with energy for a long time. SPRING: The season when the weather is slightly warm and beautiful flowers bloom. SOLAR PANEL: A device that comprises solar cells to convert sunlight into electricity. D. Complete the concept map.
Sources of Energy branches into: Examples: Sun, Wind, Water Non-renewable energy sources II. Short Answer Questions
Sunrise is when the Sun appears in the sky, marking the beginning of the day. Sunset is when the Sun disappears, marking the beginning of the night. b. Renewable and non-renewable sources of energy Renewable sources are those that will not run out and can be replenished naturally (e.g., Sun, wind, water). Non-renewable sources are limited in amount and take millions of years to form, meaning they will eventually run out (e.g., coal, petrol). Solar energy is the energy we get from the Sun, which provides us with heat and light. Plants make food through a process called photosynthesis, using sunlight, carbon dioxide from the air, and water and minerals from the soil. Name the five major seasons in India. The five major seasons in India are summer, monsoon, autumn, winter, and spring. III. Long Answer Questions
How does weather affect our life? Weather affects our life by influencing our eating and drinking habits (e.g., cold drinks in summer, hot drinks in winter), the type of clothes we wear (e.g., light cotton in summer, woollen in winter), and even the type of houses people build (e.g., sloping roofs in rainy areas, mud walls in hot areas). Write any four ways by which you can conserve energy. Switch off fans and lights when not in use. Take a short shower instead of a long one. To travel short distances, walk or use a bicycle. Open the blinds or curtains at home on sunny winter days to let the sunrays provide natural warmth. Solar energy supports life. Explain. Solar energy is crucial for life because the Sun provides the light and warmth necessary for all living things to survive. Plants use solar energy through photosynthesis to produce their own food, forming the base of the food chain. Without the Sun’s energy, plants wouldn’t grow, and animals (including humans) would have no food. The Sun also drives the water cycle, providing freshwater, and its heat influences weather and climate, creating habitable conditions on Earth. IV. Challenge
Which one will you choose among the following? Tick (✓) the correct picture. Winter: [Sweater image] (✓) To travel short distances: [Bicycle image] (✓) For fresh air: [Person watering sapling image] (✓) V. Enrichment
C. Case Study
Dev’s mother asked him to get a bottle of oil from a nearby market. Dev wanted to go on his bicycle. But his father insisted that they should go in the car. Whose idea will save energy—Dev’s or his father’s? Why? Dev’s idea will save energy. Using a bicycle does not consume fuel or electricity, making it an energy-efficient and pollution-free way to travel short distances. Going by car, as his father suggested, consumes fuel and contributes to energy depletion and air pollution. Science Quest
Find out how you get electricity in your home. Most homes get electricity from power plants that generate it using various sources like coal, natural gas, hydroelectric dams, nuclear power, or renewable sources like solar and wind farms, which is then transmitted through power lines. Do you use any device in your home that is run by solar power? Find out more about any one solar-powered device and make a report on it. Not applicable (activity-based/personal survey). Riddle Time
Find at least SIX words related to the Sun in the given letter grid.
Picture Survey
Which season is shown in the picture alongside? What do you wear or which object do you use to prevent getting wet in the rain? Name one animal that loves this season. Name the colours in the rainbow. Red, Orange, Yellow, Green, Blue, Indigo, Violet. 
Answers to textbook exercises
