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1l the quest for political stability: germany, 1871-1991
Britain & the wider world: 1745 -1901
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Inter-war germany
Medieval period: 1066 -1509
2d religious conflict and the church in england, c1529-c1570
2o democracy and nazism: germany, 1918-1945
1f industrialisation and the people: britain, c1783-1885
1c the tudors: england, 1485-1603
2m wars and welfare: britain in transition, 1906-1957
World war two & the holocaust
2n revolution and dictatorship: russia, 1917-1953
2s the making of modern britain, 1951-2007
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Physics
27 Nov 2025
64
3 pages
;) @pookiepie1234
Energy is everywhere around us - from the food you eat to your phone battery to a football... Show more
Your world is packed with energy stores - different ways energy gets tucked away, ready to be used. Think of chemical energy as the power hiding in your lunch, petrol, or your phone battery, just waiting to fuel action.
When objects move, they've got kinetic energy - whether it's you running or a car speeding down the motorway. Meanwhile, thermal energy lives inside all objects, making them warm or hot to touch.
Elastic potential energy builds up when you stretch a rubber band, squash a spring, or twist something out of shape. Gravitational potential energy exists whenever objects sit high up - like a book on a shelf or you at the top of a slide.
Quick Tip Remember that energy never just sits there doing nothing - it's constantly moving between these different stores through heating, forces, sound, light, and electricity!
Here's the golden rule that'll help you ace physics energy can never be created or destroyed. This brilliant concept is called the law of conservation of energy, and it means energy only moves from one store to another.
Picture an electric kettle as a simple energy system. The total energy going in always equals the total energy coming out - it's perfectly balanced. We measure all this energy movement in Joules (J).
Energy diagrams make this concept dead easy to visualise. When a car brakes, kinetic energy (from the moving car) transfers through forces into thermal energy (hot brakes). Similarly, when a bullet hits an egg, the bullet's kinetic energy transfers through impact forces into heat, sound, and kinetic energy of the broken eggshell.
Remember Energy is always conserved, but it doesn't always transfer into forms that are actually useful to us!
Sankey diagrams are brilliant visual tools that show exactly how much energy transfers in any system. The width of each arrow represents the amount of energy measured in Joules - wider arrows mean more energy.
Looking at the example, 100J of electrical energy enters the system. Then it splits 55J transfers as light energy whilst 45J transfers through heating.
These diagrams make energy transfers crystal clear and help you track where every single Joule goes. You'll find them incredibly useful for solving energy problems and understanding efficiency in real-world devices.
Pro Tip The total width of arrows going out always equals the width of arrows going in - that's conservation of energy in action!
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
1
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the fundamental concepts of energy conservation, energy resources, and energy transfer mechanisms. This summary covers key topics such as renewable and non-renewable energy, efficiency equations, and methods to reduce energy loss. Ideal for AQA Physics Unit 4.1 - Energy (Higher).
PhysicsExplore key concepts in electricity and energy, including resistance, Ohm's Law, energy resources, and the principles of circuits. This summary covers essential topics for GCSE combined science AQA Trilogy, providing a clear understanding of how electrical systems operate and the conservation of energy. Ideal for exam preparation and revision.
PhysicsExplore the fundamentals of energy flow diagrams, including energy stores, pathways, and transfers. This summary covers key concepts such as heating, electrical transfer, and the eight energy stores, providing a clear understanding of how energy is measured and transformed in various systems. Ideal for students studying energy principles in physics.
PhysicsExplore key concepts in electricity and energy, including circuit fundamentals, Ohm's Law, renewable vs non-renewable resources, and energy transfers. This summary covers series and parallel circuits, power calculations, and methods to reduce energy waste, making it essential for GCSE Physics students preparing for exams.
PhysicsExplore the principles of work and energy in physics, including the work done formula, energy transfers, and examples of energy stores. This summary covers key concepts such as mechanical work, conservation of energy, and the Work-Energy Principle, providing a clear understanding for students. Ideal for exam preparation and quick reference.
PhysicsExplore the principles of energy transfer, including gravitational potential energy, kinetic energy, and elastic potential energy. This summary covers key concepts such as work done, efficiency, and the impact of friction on energy dissipation. Ideal for GCSE AQA Physics students seeking to understand energy transformations and conservation.
PhysicsApp Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
;)
@pookiepie1234
Energy is everywhere around us - from the food you eat to your phone battery to a football flying through the air. Understanding how energy works and moves between different forms is crucial for mastering physics and explaining how our... Show more
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Your world is packed with energy stores - different ways energy gets tucked away, ready to be used. Think of chemical energy as the power hiding in your lunch, petrol, or your phone battery, just waiting to fuel action.
When objects move, they've got kinetic energy - whether it's you running or a car speeding down the motorway. Meanwhile, thermal energy lives inside all objects, making them warm or hot to touch.
Elastic potential energy builds up when you stretch a rubber band, squash a spring, or twist something out of shape. Gravitational potential energy exists whenever objects sit high up - like a book on a shelf or you at the top of a slide.
Quick Tip: Remember that energy never just sits there doing nothing - it's constantly moving between these different stores through heating, forces, sound, light, and electricity!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Here's the golden rule that'll help you ace physics: energy can never be created or destroyed. This brilliant concept is called the law of conservation of energy, and it means energy only moves from one store to another.
Picture an electric kettle as a simple energy system. The total energy going in always equals the total energy coming out - it's perfectly balanced. We measure all this energy movement in Joules (J).
Energy diagrams make this concept dead easy to visualise. When a car brakes, kinetic energy (from the moving car) transfers through forces into thermal energy (hot brakes). Similarly, when a bullet hits an egg, the bullet's kinetic energy transfers through impact forces into heat, sound, and kinetic energy of the broken eggshell.
Remember: Energy is always conserved, but it doesn't always transfer into forms that are actually useful to us!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Sankey diagrams are brilliant visual tools that show exactly how much energy transfers in any system. The width of each arrow represents the amount of energy measured in Joules - wider arrows mean more energy.
Looking at the example, 100J of electrical energy enters the system. Then it splits: 55J transfers as light energy whilst 45J transfers through heating.
These diagrams make energy transfers crystal clear and help you track where every single Joule goes. You'll find them incredibly useful for solving energy problems and understanding efficiency in real-world devices.
Pro Tip: The total width of arrows going out always equals the width of arrows going in - that's conservation of energy in action!
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
1
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the fundamental concepts of energy conservation, energy resources, and energy transfer mechanisms. This summary covers key topics such as renewable and non-renewable energy, efficiency equations, and methods to reduce energy loss. Ideal for AQA Physics Unit 4.1 - Energy (Higher).
PhysicsExplore key concepts in electricity and energy, including resistance, Ohm's Law, energy resources, and the principles of circuits. This summary covers essential topics for GCSE combined science AQA Trilogy, providing a clear understanding of how electrical systems operate and the conservation of energy. Ideal for exam preparation and revision.
PhysicsExplore the fundamentals of energy flow diagrams, including energy stores, pathways, and transfers. This summary covers key concepts such as heating, electrical transfer, and the eight energy stores, providing a clear understanding of how energy is measured and transformed in various systems. Ideal for students studying energy principles in physics.
PhysicsExplore key concepts in electricity and energy, including circuit fundamentals, Ohm's Law, renewable vs non-renewable resources, and energy transfers. This summary covers series and parallel circuits, power calculations, and methods to reduce energy waste, making it essential for GCSE Physics students preparing for exams.
PhysicsExplore the principles of work and energy in physics, including the work done formula, energy transfers, and examples of energy stores. This summary covers key concepts such as mechanical work, conservation of energy, and the Work-Energy Principle, providing a clear understanding for students. Ideal for exam preparation and quick reference.
PhysicsExplore the principles of energy transfer, including gravitational potential energy, kinetic energy, and elastic potential energy. This summary covers key concepts such as work done, efficiency, and the impact of friction on energy dissipation. Ideal for GCSE AQA Physics students seeking to understand energy transformations and conservation.
PhysicsApp Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
