Maths
Biology
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English Language
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Responding to change (a2 only)
Infection and response
Homeostasis and response
Energy transfers (a2 only)
Cell biology
Organisms respond to changes in their internal and external environments (a-level only)
Biological molecules
Organisation
Substance exchange
Bioenergetics
Genetic information & variation
Inheritance, variation and evolution
Genetics & ecosystems (a2 only)
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1l the quest for political stability: germany, 1871-1991
Britain & the wider world: 1745 -1901
The cold war
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
World war one
Britain: 1509 -1745
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Physics
3 Dec 2025
283
6 pages
Somaia S @somaia
Energy is everywhere around us - from the kinetic energy in your moving phone to the thermal energy... Show more
Think of energy like money in different bank accounts - it can move between accounts but never disappears completely. There are eight main energy stores you need to know kinetic (anything moving), thermal (heat in objects), chemical (stored in fuels and food), gravitational potential (objects with height), elastic potential (stretched or compressed things), electrostatic (charged objects), magnetic (magnets), and nuclear (inside atoms).
Energy transfers happen in four key ways mechanically (forces doing work), by heating (temperature differences), electrically (moving charges), and by radiation (like light or radio waves). When physicists talk about work done, they simply mean energy transferred - it's the same thing with a different name.
The conservation of energy principle is absolutely fundamental - energy can never be created or destroyed, only transferred between stores or dissipated as waste. In any closed system, the total amount of energy always stays exactly the same, even though some gets "wasted" during transfers.
Key Point Energy is like money - it can change hands but the total amount never changes!
You'll need three crucial equations for your exams. Kinetic energy uses Ek = ½mv², where m is mass in kg and v is speed in m/s. Gravitational potential energy follows Ep = mgh, with m as mass, g as gravitational field strength , and h as height in metres.
Elastic potential energy in springs uses Ee = ½ke², where k is the spring constant and e is the extension. These aren't just random formulas - they describe real energy transformations happening constantly around you.
The beauty of these equations becomes clear when objects move between energy stores. When you drop a ball, energy lost from the gravitational potential store equals energy gained in the kinetic store (ignoring air resistance). This energy transfer principle explains everything from roller coasters to bouncing balls.
Exam Tip Always check your units match the formula - mass in kg, speed in m/s, and height in metres!
Specific heat capacity (SHC) tells you how much energy you need to heat up 1kg of material by 1°C. Different materials need vastly different amounts of energy - water needs loads of energy to heat up, which is why the sea stays fairly cool in summer.
The equation ΔE = mcΔθ connects energy change, mass, specific heat capacity, and temperature change. This formula explains why small pans of water boil faster than large ones, and why metal spoons get hot in your tea whilst plastic ones don't.
In the required practical, you'll heat a metal block whilst measuring temperature changes over time. The key trick is wrapping the block in insulation to prevent energy escaping, and keeping the current constant throughout. You calculate the energy transferred using E = Pt , then use your temperature measurements to work out the material's specific heat capacity.
Practical Tip Keep checking that ammeter - if the current changes, your results won't be reliable!
Power measures how quickly energy transfers happen - it's the rate of doing work measured in watts (W). A 1000W kettle transfers 1000 joules every second, making it much faster than a 100W bulb. Use P = E/t or P = W/t to calculate power from energy or work done.
Conduction happens when vibrating particles bump into their neighbours, passing energy along like a domino effect. Materials with high thermal conductivity transfer energy quickly (like metals), whilst insulators have low conductivity.
Convection works differently - energetic particles actually move from hot regions to cooler ones, carrying energy with them. This creates circulation patterns in fluids like air and water, explaining why hot air rises and cold air sinks.
Real-world Connection Your radiators use convection currents to heat rooms - warm air rises, cools down, then sinks back down to be heated again!
Thermal insulation works by slowing down unwanted energy transfers. The thicker your walls and the lower their thermal conductivity, the better they'll keep heat in during winter.
Cavity walls have air gaps between inner and outer walls, loft insulation traps air pockets in glass fibres, and double glazing prevents conduction through windows. Draught-proofing stops air currents, whilst thick curtains add an extra barrier.
In the required practical, you'll test different insulating materials by timing how quickly hot water cools down. The key is using identical masses of water and starting temperatures each time - only the wrapping material should change between tests.
Money-saving Tip Good insulation pays for itself - less energy wasted means lower heating bills!
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.
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Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore key physics concepts related to energy, including energy sources, transfers, and efficiency. This summary covers essential equations and principles such as the work-energy theorem, gravitational potential energy, and specific heat capacity. Ideal for students preparing for exams or seeking to deepen their understanding of energy in physics.
PhysicsExplore 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 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 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.
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
Somaia S
@somaia
Energy is everywhere around us - from the kinetic energy in your moving phone to the thermal energy warming your morning tea. Understanding how energy moves between different stores and transfers through various methods is crucial for explaining everything from... Show more
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Think of energy like money in different bank accounts - it can move between accounts but never disappears completely. There are eight main energy stores you need to know: kinetic (anything moving), thermal (heat in objects), chemical (stored in fuels and food), gravitational potential (objects with height), elastic potential (stretched or compressed things), electrostatic (charged objects), magnetic (magnets), and nuclear (inside atoms).
Energy transfers happen in four key ways: mechanically (forces doing work), by heating (temperature differences), electrically (moving charges), and by radiation (like light or radio waves). When physicists talk about work done, they simply mean energy transferred - it's the same thing with a different name.
The conservation of energy principle is absolutely fundamental - energy can never be created or destroyed, only transferred between stores or dissipated as waste. In any closed system, the total amount of energy always stays exactly the same, even though some gets "wasted" during transfers.
Key Point: Energy is like money - it can change hands but the total amount never changes!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
You'll need three crucial equations for your exams. Kinetic energy uses Ek = ½mv², where m is mass in kg and v is speed in m/s. Gravitational potential energy follows Ep = mgh, with m as mass, g as gravitational field strength , and h as height in metres.
Elastic potential energy in springs uses Ee = ½ke², where k is the spring constant and e is the extension. These aren't just random formulas - they describe real energy transformations happening constantly around you.
The beauty of these equations becomes clear when objects move between energy stores. When you drop a ball, energy lost from the gravitational potential store equals energy gained in the kinetic store (ignoring air resistance). This energy transfer principle explains everything from roller coasters to bouncing balls.
Exam Tip: Always check your units match the formula - mass in kg, speed in m/s, and height in metres!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Specific heat capacity (SHC) tells you how much energy you need to heat up 1kg of material by 1°C. Different materials need vastly different amounts of energy - water needs loads of energy to heat up, which is why the sea stays fairly cool in summer.
The equation ΔE = mcΔθ connects energy change, mass, specific heat capacity, and temperature change. This formula explains why small pans of water boil faster than large ones, and why metal spoons get hot in your tea whilst plastic ones don't.
In the required practical, you'll heat a metal block whilst measuring temperature changes over time. The key trick is wrapping the block in insulation to prevent energy escaping, and keeping the current constant throughout. You calculate the energy transferred using E = Pt , then use your temperature measurements to work out the material's specific heat capacity.
Practical Tip: Keep checking that ammeter - if the current changes, your results won't be reliable!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Power measures how quickly energy transfers happen - it's the rate of doing work measured in watts (W). A 1000W kettle transfers 1000 joules every second, making it much faster than a 100W bulb. Use P = E/t or P = W/t to calculate power from energy or work done.
Conduction happens when vibrating particles bump into their neighbours, passing energy along like a domino effect. Materials with high thermal conductivity transfer energy quickly (like metals), whilst insulators have low conductivity.
Convection works differently - energetic particles actually move from hot regions to cooler ones, carrying energy with them. This creates circulation patterns in fluids like air and water, explaining why hot air rises and cold air sinks.
Real-world Connection: Your radiators use convection currents to heat rooms - warm air rises, cools down, then sinks back down to be heated again!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Thermal insulation works by slowing down unwanted energy transfers. The thicker your walls and the lower their thermal conductivity, the better they'll keep heat in during winter.
Cavity walls have air gaps between inner and outer walls, loft insulation traps air pockets in glass fibres, and double glazing prevents conduction through windows. Draught-proofing stops air currents, whilst thick curtains add an extra barrier.
In the required practical, you'll test different insulating materials by timing how quickly hot water cools down. The key is using identical masses of water and starting temperatures each time - only the wrapping material should change between tests.
Money-saving Tip: Good insulation pays for itself - less energy wasted means lower heating bills!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
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.
6
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore key physics concepts related to energy, including energy sources, transfers, and efficiency. This summary covers essential equations and principles such as the work-energy theorem, gravitational potential energy, and specific heat capacity. Ideal for students preparing for exams or seeking to deepen their understanding of energy in physics.
PhysicsExplore 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 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 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.
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
