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Britain & the wider world: 1745 -1901
1l the quest for political stability: germany, 1871-1991
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
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2s the making of modern britain, 1951-2007
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Physics
16 Dec 2025
44
2 pages
Polar @polar
Understanding ideal gases is crucial for mastering how temperature, pressure, and volume work together in physics. You'll learn... Show more
Ever wondered why a balloon shrinks in cold weather or why a bike pump gets hot when you use it? The ideal gas equation explains it all PV = NkT. This powerful formula connects pressure (P), volume (V), number of molecules (N), and temperature (T) through Boltzmann's constant .
Real gases behave like ideal gases under normal conditions because molecules follow five key assumptions. Particles move randomly and continuously, don't attract each other, and take up negligible space compared to their container. Most importantly, collisions are elastic - no kinetic energy gets lost when molecules bounce around.
Quick Tip Remember that temperature in the ideal gas equation must always be in Kelvin, not Celsius!
The kinetic theory brilliantly explains pressure changes. When you decrease volume, more molecules hit the container walls per second, increasing pressure. Similarly, heating a gas makes molecules move faster, creating more forceful collisions and higher pressure.
Kinetic and potential energy calculations are your toolkit for solving gas problems. Kinetic energy uses KE = ½mv², whilst potential energy follows PE = mgh. You can rearrange these formulas to find velocity v = √.
Let's tackle real problems! For gas calculations, use the combined gas law when dealing with changing conditions. If pressure increases from 101 kPa to 303 kPa whilst volume changes and temperature rises, you'll need T₂ = (P₁V₁T₁)/(P₂V₂).
Exam Strategy Always convert Celsius to Kelvin by adding 273 - this catches many students out!
Motion problems become straightforward once you identify what you're solving for. A bird with 0.25 kg mass and 40.5 J kinetic energy has velocity v = √(2×40.5/0.25) = 18 m/s. Practice rearranging formulas before your exam - it's often the difference between getting stuck and sailing through questions.
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 detailed solutions to the OCR A-Level Physics November 2020 paper. This resource covers key concepts such as mechanics, thermodynamics, wave behavior, and the principles of energy transfer. Ideal for students preparing for exams, it includes worked examples on topics like Hooke's Law, simple harmonic motion, and gravitational forces. Enhance your understanding and boost your exam performance with this comprehensive guide.
PhysicsComprehensive study notes on mechanics, covering key concepts such as momentum, projectile motion, Newton's laws, energy conservation, and kinematic equations. Ideal for AQA A Level Physics revision, including practice questions and detailed explanations of mechanics principles.
PhysicsExplore the principles of projectile motion, including the independence of horizontal and vertical components, free fall dynamics, and the effects of air resistance. This summary covers key concepts such as terminal velocity and friction, providing a clear understanding of how these factors influence motion. Ideal for A-Level Physics students.
PhysicsExplore the fundamentals of centripetal motion in this A Level Physics summary. Understand key concepts such as centripetal acceleration, angular velocity, and the forces involved in circular motion. Ideal for AQA students preparing for exams, this resource covers essential equations and principles of rotational dynamics.
PhysicsExplore key concepts in Mechanics and Materials for AQA A-Level Physics, including Newton's Laws, energy conservation, kinematic equations, and projectile motion. This summary covers essential principles such as static equilibrium, elastic potential energy, and the work-energy principle, providing a comprehensive understanding for Year 12 and Year 13 students.
PhysicsExplore detailed solutions to the OCR A Level Physics June 2018 paper, covering key concepts such as Newtonian Mechanics, Circular Motion, Gravitational Fields, and more. This comprehensive resource includes worked examples and explanations for each question, making it an essential study tool for mastering physics concepts and exam preparation.
PhysicsQuotes from every main character
English LiteratureApp 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
Polar
@polar
Understanding ideal gases is crucial for mastering how temperature, pressure, and volume work together in physics. You'll learn the fundamental equation that governs gas behaviour and see how molecular motion explains everyday phenomena like inflating tyres and heating up containers.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Ever wondered why a balloon shrinks in cold weather or why a bike pump gets hot when you use it? The ideal gas equation explains it all: PV = NkT. This powerful formula connects pressure (P), volume (V), number of molecules (N), and temperature (T) through Boltzmann's constant .
Real gases behave like ideal gases under normal conditions because molecules follow five key assumptions. Particles move randomly and continuously, don't attract each other, and take up negligible space compared to their container. Most importantly, collisions are elastic - no kinetic energy gets lost when molecules bounce around.
Quick Tip: Remember that temperature in the ideal gas equation must always be in Kelvin, not Celsius!
The kinetic theory brilliantly explains pressure changes. When you decrease volume, more molecules hit the container walls per second, increasing pressure. Similarly, heating a gas makes molecules move faster, creating more forceful collisions and higher pressure.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Kinetic and potential energy calculations are your toolkit for solving gas problems. Kinetic energy uses KE = ½mv², whilst potential energy follows PE = mgh. You can rearrange these formulas to find velocity: v = √.
Let's tackle real problems! For gas calculations, use the combined gas law when dealing with changing conditions. If pressure increases from 101 kPa to 303 kPa whilst volume changes and temperature rises, you'll need T₂ = (P₁V₁T₁)/(P₂V₂).
Exam Strategy: Always convert Celsius to Kelvin by adding 273 - this catches many students out!
Motion problems become straightforward once you identify what you're solving for. A bird with 0.25 kg mass and 40.5 J kinetic energy has velocity v = √(2×40.5/0.25) = 18 m/s. Practice rearranging formulas before your exam - it's often the difference between getting stuck and sailing through questions.
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 detailed solutions to the OCR A-Level Physics November 2020 paper. This resource covers key concepts such as mechanics, thermodynamics, wave behavior, and the principles of energy transfer. Ideal for students preparing for exams, it includes worked examples on topics like Hooke's Law, simple harmonic motion, and gravitational forces. Enhance your understanding and boost your exam performance with this comprehensive guide.
PhysicsComprehensive study notes on mechanics, covering key concepts such as momentum, projectile motion, Newton's laws, energy conservation, and kinematic equations. Ideal for AQA A Level Physics revision, including practice questions and detailed explanations of mechanics principles.
PhysicsExplore the principles of projectile motion, including the independence of horizontal and vertical components, free fall dynamics, and the effects of air resistance. This summary covers key concepts such as terminal velocity and friction, providing a clear understanding of how these factors influence motion. Ideal for A-Level Physics students.
PhysicsExplore the fundamentals of centripetal motion in this A Level Physics summary. Understand key concepts such as centripetal acceleration, angular velocity, and the forces involved in circular motion. Ideal for AQA students preparing for exams, this resource covers essential equations and principles of rotational dynamics.
PhysicsExplore key concepts in Mechanics and Materials for AQA A-Level Physics, including Newton's Laws, energy conservation, kinematic equations, and projectile motion. This summary covers essential principles such as static equilibrium, elastic potential energy, and the work-energy principle, providing a comprehensive understanding for Year 12 and Year 13 students.
PhysicsExplore detailed solutions to the OCR A Level Physics June 2018 paper, covering key concepts such as Newtonian Mechanics, Circular Motion, Gravitational Fields, and more. This comprehensive resource includes worked examples and explanations for each question, making it an essential study tool for mastering physics concepts and exam preparation.
PhysicsQuotes from every main character
English LiteratureApp 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
Sociology