CBSE Class 5 · Science
Energy — How Things Work
Official NCERT chapter from Our Wondrous World (book code eeev1). ExamMaster notes are original teaching at CBSE Class 5 depth.
This lesson follows the official chapter “Energy — How Things Work” in Our Wondrous World. The words below are ExamMaster’s teaching, not a paste from the book. Use the NCERT chapter for the classroom sequence; use these notes to hold the idea without copying exercises or figures.
- CBSE Class 5
- Easy level
- 8 concepts
1Energy makes a change you can name
Energy is what you name when a cause pays for a change: the lamp lights, the fan moves, the pot heats. No named change, no energy-story yet.
A brand is not energy.
Figure. Energy is named by a change you can point at. Still to moving is one such change.
How it works
- Name the changeLights, moves, heats.
- Name what paid for it at this classEnergy from the socket, the flame, the wound spring.
- If you cannot name a change, you have not startedLook again.
2Different forms of energy at home
Light, heat, movement, sound — forms you can sort by the change you notice. A lamp is a light-change; a stove is a heat-change.
One object can show more than one form (a mixer: movement and sound).
Figure. Heat, light, and motion are three forms you meet at home. The form is the job, not the gadget name.
How it works
- Pick an objectLamp, stove, mixer.
- Name the change you noticeLight, heat, move, sound.
- Allow two forms on one objectTwo ticks.
3A fan, a stove, and a lamp use energy differently
Fan: movement. Stove: heat. Lamp: light. Same word “uses energy”, three different changes.
Do not mash them into one gadget-word.
Figure. The same word energy, three different changes: air moves, a pan heats, a room lights.
How it works
- Name the objectFan, stove, or lamp.
- Name its main changeMove, heat, or light.
- Keep the three apartDifferent uses.
4Clean and efficient use is a choice
Switch off a fan you are not using. That is less waste for the same later job. Efficient means the change you wanted with less leftover waste.
Skipping the needed lamp at night is not this saving.
Figure. Efficient use keeps more of the bar as useful light. The old lamp wastes most of its 10 parts as heat.
How it works
- Name the wanted changeCool the room, or see.
- See unused runningWaste.
- Stop unused runningSame job later, less waste now.
5Work is the change energy pays for
Work here is the named change: water lifted, toy moved, grain ground. Energy is what you say paid for that work.
A resting toy is not doing this work.
Figure. Work is the change energy pays for. The lift from floor to shelf is the work, not the word on the page.
How it works
- Name the workThe change.
- Name that energy paid for itThe story.
- Do not call a brand “work”Change first.
6A toy that moves has an energy story
A wound spring, a battery, or a push — name where the move was paid from. Then the wheels change place.
“It is magic” is not the story.
Figure. A wind-up toy stores energy in the spring, then spends it as a roll. The story is store, then spend.
How it works
- Name the pay-source at this classSpring, battery, push.
- Name the changeIt moves.
- Link themEnergy story.
Wound toy
A toy car moves after you wind a key, then stops. What paid for the move, and what was the change?
- Pay-sourcethe wound spring
- Changethe car moved
- When it stopsthat pay-source is used up for now
Pro tip. Name pay-source and change. A brand on the toy is not the story.
7One classroom case
One lamp you switched, or one toy you wound, is enough. You do not need every appliance in a shop.
A case with change and pay-source beats a list of brands.
Figure. A lever is a bar on a fulcrum. Effort on one side lifts the load on the other.
How it works
- Pick one thingThis lamp, this toy.
- Name change and pay-sourceThe case.
- StopNo shop tour.
8A miss: naming the brand as the energy
“It works because it is Brand X” names a shop, not a change or a pay-source. Peel the brand.
The miss is stopping at the sticker.
Figure. The brand on a cell is a name. The energy is the chemical store that can become electric, heat, or light.
How it works
- Hear a brandA shop word.
- Ask change and pay-sourceThe science.
- If only the brand remains, call the missNo energy-story.
A lamp lighting is
- A light-change energy paid for
- A brand
- A river
Name the change first.
Notes
- Mapped to the official NCERT chapter “Energy — How Things Work”. Original teaching only — no textbook sentences.
- Science here is Physics, Chemistry and Biology ideas at this class, never a language or social-science chapter.
Recap
Hold these pegs from the official chapter “Energy — How Things Work”. The wording is ExamMaster’s teaching, not a textbook recap.
- Energy makes a change you can name
- Energy is what you name when a cause pays for a change: the lamp lights, the fan moves, the pot heats.
- Different forms of energy at home
- Light, heat, movement, sound — forms you can sort by the change you notice.
- A fan, a stove, and a lamp use energy differently
- Fan: movement. Stove: heat. Lamp: light. Same word “uses energy”, three different changes.
- Clean and efficient use is a choice
- Switch off a fan you are not using. That is less waste for the same later job. Efficient means the change you wanted with less leftover waste.
- Work is the change energy pays for
- Work here is the named change: water lifted, toy moved, grain ground.
- A toy that moves has an energy story
- A wound spring, a battery, or a push — name where the move was paid from.
Practise Energy — How Things Work
Reading is free and needs no account. Practice, mocks and progress live in the app.
- A 4-question practice set that ends the chapter
- 1 quick check with worked explanations
- Timed mocks scored with the real marking scheme
- Readiness tracked per topic, kept on your device