pearsons sciens yr* chap 5.1

5.1.1 What does energy do?

• Energy is the capacity to make things happen — to move something, heat it up, change its shape, produce sound or light. ([garyturnerscience.com][1])

• You can’t see energy directly, but you can observe its effects: e.g., a roller-coaster cart heating its wheels, wind rushing past your hair. ([garyturnerscience.com][1])

• The term “work” in science means when an object is shifted or forced to change shape — in other words, when energy is used. ([garyturnerscience.com][1])

• Practice question: Describe an everyday example where energy makes something happen (i.e., use “work” in the sense of shifting or changing shape).

• There are many forms of energy — some common ones:

• Kinetic energy: energy of movement. ([garyturnerscience.com][1])

• Heat (thermal) energy: from Sun, flames, electrical devices, even living creatures. ([garyturnerscience.com][1])

• Light energy: from the Sun, light globes, fires, creatures like glow-worms. ([garyturnerscience.com][1])

• Sound energy: energy of vibrating air (or medium) particles, interpreted by ears/brain. ([garyturnerscience.com][1])

• Electrical energy: from power stations, solar cells, batteries, and lightning. ([garyturnerscience.com][1])

• Measuring energy: The unit is the joule (J). ([kaizeneducation.online][2])

• Because one joule is small, larger amounts use kilojoules (kJ = 1 000 J) or megajoules (MJ = 1 000 000 J). ([StudyRes][3])

• Convert 2 kJ into joules: 2 kJ = 2 × 1 000 = 2 000 J. ([garyturnerscience.com][1])

• Convert 3.5 MJ into joules: 3.5 × 1 000 000 = 3 500 000 J. ([garyturnerscience.com][1])

• Practice question: If a device uses 4 800 000 J of energy, how many megajoules is that?

5.1.3 Stored energy (Potential energy)

• Many objects have stored (potential) energy: energy which isn’t being used right now, but has the potential to do work later. ([kaizeneducation.online][2])

• Types of stored energy include:

• Gravitational potential energy: stored when an object is above the ground. The higher it is, the more this energy. ([garyturnerscience.com][1])

• Chemical potential energy: energy stored in substances (fuel, food, batteries). When consumed/burned/digested, this energy is released. ([kaizeneducation.online][2])

• Elastic potential energy: energy stored in stretched or compressed objects (springs, rubber bands). ([kaizeneducation.online][2])

• Nuclear energy: energy stored in the nucleus of atoms — released in nuclear reactions (power plants, sun, bombs). ([garyturnerscience.com][1])

• Practice question: Classify the following as gravitational, chemical, elastic or nuclear potential energy: a book on a shelf, a rubber band stretched, wood in a fire, uranium in a reactor.

5.1.4 Energy transfer, transformation & the law of conservation of energy

• Energy transfer: when energy passes from one object to another. Example: hitting a tennis ball transfers kinetic energy from bat to ball. ([kaizeneducation.online][2])

• Energy transformation: when energy changes from one form to another. Example: electrical → light + sound + heat in a television. ([kaizeneducation.online][2])

• Law of conservation of energy: Energy cannot be created or destroyed — only transferred or transformed. If energy seems to “disappear”, it has been converted into another form. ([kaizeneducation.online][2])

• Practice question: Drop a block from a height and describe what happens to its energy (what it starts as, what it becomes, where it goes) using the law of conservation of energy.

| Term | Definition |

| ---------------------------------- | ------------------------------------------------------------------------------------ |

| Energy | The capacity to do work or cause change. |

| Kinetic energy | Energy of motion/movement. |

| Potential energy | Stored energy, ready to be used. |

| Gravitational potential energy | Energy stored in an object due to its height above the ground. |

| Chemical energy | Energy stored in substances, released in reactions/digestion. |

| Elastic potential energy | Energy stored in stretched/compressed objects. |

| Nuclear energy | Energy stored in the nucleus of an atom. |

| Joule (J) | Unit of energy. |

| Energy transfer | Moving energy from one object to another. |

| Energy transformation | Changing energy from one form to another. |

| Conservation of energy | Principle that energy cannot be created or destroyed, only changed in form or place. |

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Example questions you should be able to answer

• What does energy do? Give an example in a sentence using “work”.

• List five different forms of energy and give an everyday example of each.

• Explain why energy is measured in joules and why we sometimes use kJ or MJ.

• Identify and explain three types of stored energy (potential energy) with examples.

• Given a scenario (e.g., a book falling, a stretched spring release, a car burning fuel), describe energy transfer, transformation, and apply the law of conservation of energy.

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Tips for revision / exam preparation

• Create a two-column table: Form of energy | Everyday example, and practice filling it in.

• Practice converting units (J ↔ kJ ↔ MJ) so you’re comfortable with numbers.

• Use everyday objects/processes to identify: What energy is stored? What happens when it’s released? What forms does it take?

• Explain scenarios fully: “Starting energy → change → new form(s) of energy” — this helps show understanding of transfer/transformation.

• Make sure you can use the vocabulary in sentences (not just define them). For example: “The stretched rubber band has elastic potential energy which, when released, transforms into kinetic energy of the moving object.”

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If you like, I can also generate a full set of revision flash-cards (front/back) for Chapter 5.1 ready for printing or use in an app like Quizlet/Anki. Would you like that?

[2]: https://kaizeneducation.online/courses/year-8-science-nsw-syllabus/lesson/5-1-energy-around-you/?utm_source=chatgpt.com "5.1 Energy around you - Kaizen Education"

Here are detailed revision notes for Chapter 5.1 (“Energy Around You”) of the Pearson Science 7‑10 (NSW) Student Book Year 8 text — organised by sub-section with key definitions, worked examples and practice questions.

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5.1.1 What does energy do?

• Energy is the capacity to make things happen — to move something, heat it up, change its shape, produce sound or light. ([garyturnerscience.com][1])

• You can’t see energy directly, but you can observe its effects: e.g., a roller-coaster cart heating its wheels, wind rushing past your hair. ([garyturnerscience.com][1])

• The term “work” in science means when an object is shifted or forced to change shape — in other words, when energy is used. ([garyturnerscience.com][1])

• Practice question: Describe an everyday example where energy makes something happen (i.e., use “work” in the sense of shifting or changing shape).

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5.1.2 Forms of energy & measuring energy

• There are many forms of energy — some common ones:

• Kinetic energy: energy of movement. ([garyturnerscience.com][1])

• Heat (thermal) energy: from Sun, flames, electrical devices, even living creatures. ([garyturnerscience.com][1])

• Light energy: from the Sun, light globes, fires, creatures like glow-worms. ([garyturnerscience.com][1])

• Sound energy: energy of vibrating air (or medium) particles, interpreted by ears/brain. ([garyturnerscience.com][1])

• Electrical energy: from power stations, solar cells, batteries, and lightning. ([garyturnerscience.com][1])

• Measuring energy: The unit is the joule (J). ([kaizeneducation.online][2])

• Because one joule is small, larger amounts use kilojoules (kJ = 1 000 J) or megajoules (MJ = 1 000 000 J). ([StudyRes][3])

• Worked Example:

• Convert 2 kJ into joules: 2 kJ = 2 × 1 000 = 2 000 J. ([garyturnerscience.com][1])

• Convert 3.5 MJ into joules: 3.5 × 1 000 000 = 3 500 000 J. ([garyturnerscience.com][1])