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1l the quest for political stability: germany, 1871-1991
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2d religious conflict and the church in england, c1529-c1570
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1f industrialisation and the people: britain, c1783-1885
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Physics
23 Nov 2025
109
5 pages
evie @e777
Understanding work and energy is crucial for physics - and it's simpler than you think! Work isn't just... Show more
The work done formula is your key to solving energy problems Work done (J) = force (N) × distance moved (m). This equation tells you exactly how much energy gets transferred when something moves.
Here's what makes this brilliant - work done equals energy transferred, so they're measured in the same units joules (J). Think of it like this if you lift your school bag, the work you do transfers energy to increase the bag's gravitational potential energy.
Quick Tip Remember that force is in newtons (N) and distance is in metres (m) - get these units right and you'll nail the calculation every time!
The formula works because energy can't just disappear - it always transfers from one form to another when work is done.
When a rocket launches into space, you're witnessing an amazing energy transformation! The chemical energy in the fuel converts to kinetic energy (movement) and gravitational potential energy as the rocket climbs higher.
This transfer of energy is called work - and here's the key connection work done always equals energy transferred. If 500 J of work is done, exactly 500 J of energy moves from one form to another.
Remember Work only happens when a force causes displacement (movement) - no movement means no work, even if you're straining with effort!
This principle explains why pushing against an immovable wall isn't considered work in physics, even though it feels exhausting.
Energy comes in many forms, and recognising these energy stores helps you understand the world around you. Chemical energy powers your body through food, whilst kinetic energy keeps cars moving down the road.
Gravitational potential energy sits waiting in that textbook on your shelf, ready to convert to kinetic energy if it falls. Elastic energy stores in stretched rubber bands, and thermal energy warms your morning tea.
More exotic forms include magnetic energy between magnets, electrostatic energy when you rub a balloon on your hair, and nuclear energy in radioactive materials.
Study Hack Connect each energy store to something in your daily life - it makes exam questions much easier to visualise!
Energy moves around through four main pathways electrical, radiation, mechanical, and heating transfers. Each pathway represents energy flowing from one place or form to another.
The most important rule in physics governs all of this conservation of energy. Energy can neither be created nor destroyed - it only transfers from one form to another. This principle explains everything from why perpetual motion machines don't work to how power stations generate electricity.
Exam Gold Conservation of energy appears in almost every physics topic, so master this concept and you'll understand so much more!
Understanding energy transfers helps you predict what happens in any physical situation.
Spotting when work actually happens can be tricky! Climbing a ladder counts as work because you're moving your weight against gravity. Pushing a rock 5 metres is work since you overcome friction to create movement.
However, pushing a car really hard without moving it isn't work - despite the effort, there's no displacement. Similarly, going up in a lift involves work, but the lift motor does it, not you.
A parked car obviously involves no work since nothing moves. The key test is always did a force cause movement?
Quick Check Ask yourself "Did something move because of a force?" - if yes, work was done!
This distinction between effort and actual work is crucial for physics calculations.
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.
2
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 the various forms of energy storage and transfer, including kinetic, potential, thermal, and chemical energy. Understand the law of conservation of energy and how energy is transformed within systems. This summary includes energy diagrams and Sankey diagrams to illustrate energy transfers effectively.
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 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
evie
@e777
Understanding work and energy is crucial for physics - and it's simpler than you think! Work isn't just about effort; it's about transferring energy when forces cause movement, and everything around you demonstrates these principles.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
The work done formula is your key to solving energy problems: Work done (J) = force (N) × distance moved (m). This equation tells you exactly how much energy gets transferred when something moves.
Here's what makes this brilliant - work done equals energy transferred, so they're measured in the same units: joules (J). Think of it like this: if you lift your school bag, the work you do transfers energy to increase the bag's gravitational potential energy.
Quick Tip: Remember that force is in newtons (N) and distance is in metres (m) - get these units right and you'll nail the calculation every time!
The formula works because energy can't just disappear - it always transfers from one form to another when work is done.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
When a rocket launches into space, you're witnessing an amazing energy transformation! The chemical energy in the fuel converts to kinetic energy (movement) and gravitational potential energy as the rocket climbs higher.
This transfer of energy is called work - and here's the key connection: work done always equals energy transferred. If 500 J of work is done, exactly 500 J of energy moves from one form to another.
Remember: Work only happens when a force causes displacement (movement) - no movement means no work, even if you're straining with effort!
This principle explains why pushing against an immovable wall isn't considered work in physics, even though it feels exhausting.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Energy comes in many forms, and recognising these energy stores helps you understand the world around you. Chemical energy powers your body through food, whilst kinetic energy keeps cars moving down the road.
Gravitational potential energy sits waiting in that textbook on your shelf, ready to convert to kinetic energy if it falls. Elastic energy stores in stretched rubber bands, and thermal energy warms your morning tea.
More exotic forms include magnetic energy between magnets, electrostatic energy when you rub a balloon on your hair, and nuclear energy in radioactive materials.
Study Hack: Connect each energy store to something in your daily life - it makes exam questions much easier to visualise!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Energy moves around through four main pathways: electrical, radiation, mechanical, and heating transfers. Each pathway represents energy flowing from one place or form to another.
The most important rule in physics governs all of this: conservation of energy. Energy can neither be created nor destroyed - it only transfers from one form to another. This principle explains everything from why perpetual motion machines don't work to how power stations generate electricity.
Exam Gold: Conservation of energy appears in almost every physics topic, so master this concept and you'll understand so much more!
Understanding energy transfers helps you predict what happens in any physical situation.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Spotting when work actually happens can be tricky! Climbing a ladder counts as work because you're moving your weight against gravity. Pushing a rock 5 metres is work since you overcome friction to create movement.
However, pushing a car really hard without moving it isn't work - despite the effort, there's no displacement. Similarly, going up in a lift involves work, but the lift motor does it, not you.
A parked car obviously involves no work since nothing moves. The key test is always: did a force cause movement?
Quick Check: Ask yourself "Did something move because of a force?" - if yes, work was done!
This distinction between effort and actual work is crucial for physics calculations.
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.
2
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 the various forms of energy storage and transfer, including kinetic, potential, thermal, and chemical energy. Understand the law of conservation of energy and how energy is transformed within systems. This summary includes energy diagrams and Sankey diagrams to illustrate energy transfers effectively.
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 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
