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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
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
11 Dec 2025
45
3 pages
~Sahasra~๐ @study.with.me123
Forces are everywhere around us - from the push you give a door to the pull of gravity... Show more
Forces are simply pushes or pulls that act on objects when they interact with other things. Think about kicking a football - your foot applies a force to make the ball move. Every force is measured in newtons (N), named after the famous scientist Sir Isaac Newton.
Forces come in two main types contact forces (where objects touch) and non-contact forces (where objects don't need to touch). This distinction helps us understand how different forces work in the real world.
Forces are vector quantities, which means they have both size (magnitude) and direction. This is different from scalar quantities that only have size. When drawing forces, we use arrows - longer arrows show stronger forces, and the arrow points in the direction the force acts.
Quick Tip Remember that force diagrams use arrows where 1mm might represent 1N, making it easy to compare different forces visually!
Contact forces only work when two objects are physically touching each other. You'll encounter these forces constantly in everyday life.
Tension happens when strings, ropes or rods pull on objects. Friction occurs when two surfaces slide past each other - it's what makes it harder to push a heavy box across the floor. Air resistance pushes against objects moving through air, which is why cyclists crouch down to go faster.
Upthrust is the upward force you feel when you're in water - it's what helps you float! Thrust is the driving force from engines that makes cars and planes move forward. Finally, normal reaction force is the push-back you get from surfaces - when you lean against a wall, it pushes back with equal force.
Real-World Connection Every time you walk, you're using friction between your shoes and the ground to push yourself forward!
Non-contact forces work even when objects aren't touching - pretty amazing, right? Magnetic force attracts or repels magnets and magnetic materials like iron. You've probably felt this when trying to push two magnets together the wrong way!
Electrostatic force happens between charged particles and can also attract or repel objects. Gravitational force is the most familiar non-contact force - it's what keeps you on Earth and makes things fall down. Gravity always pulls objects together, never pushes them apart.
We measure forces using a newton meter (also called a force meter). Always remember to 'zero' your newton meter before measuring - this means setting it to read zero when no force is applied. If you forget this step, all your measurements will be wrong by the same amount, creating what scientists call systematic error.
Exam Tip Practice identifying whether forces are contact or non-contact - this is a common test question that's easy marks if you know the difference!
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 โ all at your fingertips.
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Transform this note into: โ 50+ Practice Questions โ Interactive Flashcards โ Full Mock Exam โ Essay Outlines
Explore key concepts in physics including distance vs. displacement, scalar and vector quantities, and the types of forces. This summary is essential for Year 9 students preparing for assessments, providing clear definitions and examples of contact forces like friction and air resistance.
PhysicsExplore the fundamental differences between scalars and vectors in this concise overview. Learn about key concepts such as force, acceleration, and how to resolve vector quantities using Pythagoras' theorem and the parallelogram rule. Ideal for KS3 students seeking clarity on these essential physics topics.
BiologyCore information for paper 1 of physics. Edexcel
PhysicsExplore the fundamental concepts of contact and non-contact forces in physics. This summary covers key definitions, examples, and Newton's Third Law of Motion, making it essential for GCSE Physics students. Learn about friction, tension, magnetic, and gravitational forces, and how they interact in various scenarios.
PhysicsExplore the key concepts of contact and non-contact forces, including tension, friction, air resistance, and gravitational force. This summary provides essential insights for mastering the fundamentals of physics, ideal for exam preparation. Key topics include Free-Body Diagrams and the characteristics of various forces.
PhysicsThis is the aqa exam board for triple highwe
ChemistryApp 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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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
~Sahasra~๐
@study.with.me123
Forces are everywhere around us - from the push you give a door to the pull of gravity keeping your feet on the ground. Understanding forces is crucial in physics because they explain why objects move, stop, or change direction... Show more
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Forces are simply pushes or pulls that act on objects when they interact with other things. Think about kicking a football - your foot applies a force to make the ball move. Every force is measured in newtons (N), named after the famous scientist Sir Isaac Newton.
Forces come in two main types: contact forces (where objects touch) and non-contact forces (where objects don't need to touch). This distinction helps us understand how different forces work in the real world.
Forces are vector quantities, which means they have both size (magnitude) and direction. This is different from scalar quantities that only have size. When drawing forces, we use arrows - longer arrows show stronger forces, and the arrow points in the direction the force acts.
Quick Tip: Remember that force diagrams use arrows where 1mm might represent 1N, making it easy to compare different forces visually!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Contact forces only work when two objects are physically touching each other. You'll encounter these forces constantly in everyday life.
Tension happens when strings, ropes or rods pull on objects. Friction occurs when two surfaces slide past each other - it's what makes it harder to push a heavy box across the floor. Air resistance pushes against objects moving through air, which is why cyclists crouch down to go faster.
Upthrust is the upward force you feel when you're in water - it's what helps you float! Thrust is the driving force from engines that makes cars and planes move forward. Finally, normal reaction force is the push-back you get from surfaces - when you lean against a wall, it pushes back with equal force.
Real-World Connection: Every time you walk, you're using friction between your shoes and the ground to push yourself forward!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Non-contact forces work even when objects aren't touching - pretty amazing, right? Magnetic force attracts or repels magnets and magnetic materials like iron. You've probably felt this when trying to push two magnets together the wrong way!
Electrostatic force happens between charged particles and can also attract or repel objects. Gravitational force is the most familiar non-contact force - it's what keeps you on Earth and makes things fall down. Gravity always pulls objects together, never pushes them apart.
We measure forces using a newton meter (also called a force meter). Always remember to 'zero' your newton meter before measuring - this means setting it to read zero when no force is applied. If you forget this step, all your measurements will be wrong by the same amount, creating what scientists call systematic error.
Exam Tip: Practice identifying whether forces are contact or non-contact - this is a common test question that's easy marks if you know the difference!
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 โ all at your fingertips.
0
Smart Tools NEW
Transform this note into: โ 50+ Practice Questions โ Interactive Flashcards โ Full Mock Exam โ Essay Outlines
Explore key concepts in physics including distance vs. displacement, scalar and vector quantities, and the types of forces. This summary is essential for Year 9 students preparing for assessments, providing clear definitions and examples of contact forces like friction and air resistance.
PhysicsExplore the fundamental differences between scalars and vectors in this concise overview. Learn about key concepts such as force, acceleration, and how to resolve vector quantities using Pythagoras' theorem and the parallelogram rule. Ideal for KS3 students seeking clarity on these essential physics topics.
BiologyCore information for paper 1 of physics. Edexcel
PhysicsExplore the fundamental concepts of contact and non-contact forces in physics. This summary covers key definitions, examples, and Newton's Third Law of Motion, making it essential for GCSE Physics students. Learn about friction, tension, magnetic, and gravitational forces, and how they interact in various scenarios.
PhysicsExplore the key concepts of contact and non-contact forces, including tension, friction, air resistance, and gravitational force. This summary provides essential insights for mastering the fundamentals of physics, ideal for exam preparation. Key topics include Free-Body Diagrams and the characteristics of various forces.
PhysicsThis is the aqa exam board for triple highwe
ChemistryApp 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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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