Energy, How Things Work Chapter Notes | Our Wondrous World Class 5 - New NCERT PDF Download

Get ready to explore the exciting world of energy that powers our lives! 

What is Energy?

Let us observe a kitchen for some time. Write your observations

From observations of nature and society, here are three things we can notice for each category:

Moving- Wind rustling leaves, Cars are driving on roads, Birds flying in flocks.
Providing Light- Sun lighting the Earth, Streetlights glowing at night, Fireflies twinkling in fields.
Making a Sound- Thunder booming in storms, Voices buzzing in markets, Crickets chirping at night.
Making Things Cool- Breezes cooling lakesides, Air conditioners chilling rooms, Tree shade lowering temperatures.
Making Things Hot- Sun heating roads, Stoves cooking food, Furnaces melting metals.

• The Sun gives light and heat, making plants grow and days bright.
• Energy makes things move, light up, produce sound, or change temperature.
• We use energy every day for work, play, and many activities.

Do you know?
In parts of Himachal Pradesh, Uttarakhand, and Ladakh, people house cattle on the ground floor, with families living above. The animals’ body heat warms the upper rooms during winter, a smart, energy-saving method to stay warm without extra firewood or electricity.

The Bhadla Solar Park in Rajasthan is one of the largest solar power plants in the world.

Sources of Energy

The teacher leads a fun activity to learn where energy comes from. Let’s join in!

• The teacher asks if students ate breakfast, then has them stretch, jump, and run.
• Students feel tired when hungry but active after eating, thanks to the energy from food.
• Food gives energy to move, play, and work, keeping us strong.

Do you know?
Our brain uses energy even when we are simply sitting, sleeping or thinking.

• Animals, like dogs running or birds flying, need energy to move and survive.
• They get energy from the food they eat, just like humans.
• Food is a source of energy for all living things.

Energy from Fuel

Vehicles move and stoves cook, all powered by fuels. Let’s explore how!

• Fuels like petrol and diesel give energy to vehicles, making them move.
• Cooking gas is a fuel used in homes to cook food.
• Burning wood or coal produces smoke and pollution, so it should be used carefully.
• Oil fuels diyas, lighting up homes for special occasions.

Cochin International Airport in Kerala is the world's first airport to be entirely powered by solar energy.

Electricity

Electricity lights up our world, but it needs careful use. Let’s find out more!

Homes use electricity for fans, lights, TVs, and other things. Electricity helps create movement, sound, light, and heat in our devices.

• Modern life is highly dependent on electricity, but it must be used with care for safety.
• Schools and industries use electricity to run machines for producing clothes, toys, and books.
• Electricity makes life easier, but it can be dangerous if not used carefully.
• Most electricity comes from burning coal, which creates smoke and harmful gases.
• This polluted air harms our health and the environment.
• Other sources can produce electricity without pollution, waiting to be explored.

Do you know?
Energy efficiency, like using LED bulbs, means using less electricity for the same amount of work.

In hilly areas, watermills called gharaats use flowing water to grind grains.

Generating Energy from Sun, Wind, and Water

The Sun is the main source of energy for life on Earth.

Do you know?

Ancient ships with large sails harnessed wind energy to navigate vast seas, enabling traders from Gujarat and Tamil Nadu to reach Africa, Arabia, and Southeast Asia.

The Sun, wind, and water give us clean energy. Let’s see how they work!

• Solar panels capture sunlight to make electricity without pollution.
• Windmills spin with the wind to generate electricity cleanly.
• Fast-moving rivers or falling water can produce electricity too.
• These sources, unlike coal, don’t harm the Earth with smoke or waste.
• Some vehicles can also run on electricity now.

The Sun gives more energy to Earth in one hour than what all humans on Earth use in a whole year.

• Energy makes the world alive and active.
• Energy powers everything around us, from living beings and machines to lighting our homes.
• Clean energy from these sources is better for the planet since it does not create harmful smoke or waste.

Do you know?

Vaastu Shastra, an ancient Indian architectural system, designs buildings to align with natural energies like sunlight, wind, and heat. Strategic placement of rooms, doors, windows, and open spaces like courtyards ensures homes are bright, airy, and energy-efficient across seasons.

Some plants in deserts open only at night to save water and energy—smart nature tricks!