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3 Jan 2026
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Comprehensive Circular Motion Notes for A-Level Physics
Yasmina Taleb Medarova
@yasminatalebmedarova_ipfc
1 / 3
Understanding Radians and Circular Motion
Here's something that'll make angles much clearer: radians are simply the angle you get when the arc length equals the radius. Think of it like wrapping the radius around the circle's edge.
The key formula is θ = S/r, where θ is the angle in radians, S is the arc length, and r is the radius. For one complete revolution, you always get 2π radians (roughly 6.28), which equals 360 degrees.
Converting between radians and degrees is straightforward: multiply radians by 180/π to get degrees, or multiply degrees by π/180 to get radians. You'll use this constantly in physics calculations.
Quick tip: Remember that even though an object moves at constant speed in circular motion, its velocity constantly changes direction, which means it's always accelerating!
Key Equations for Circular Motion
The maths behind circular motion involves four crucial quantities that work together beautifully. Linear velocity (v) measures how fast the object moves along the circular path, calculated as v = 2πr/T or v = 2πfr.
Angular velocity (ω) tells you how quickly the angle changes, using ω = 2π/T = 2πf. The brilliant connection between linear and angular velocity is simply v = ωr.
Centripetal acceleration always points towards the centre and equals a = v²/r = ω²r. This acceleration needs a force to maintain it - the centripetal force F = mv²/r = mω²r.
Remember: Centripetal force isn't a new type of force - it's just whatever force (tension, friction, gravity) that keeps the object moving in a circle!
Investigating Circular Motion Practically
Want to see circular motion in action? The classic experiment involves whirling a bung (rubber stopper) attached to string through a tube, with weights hanging from the other end.
You keep the radius constant using a paperclip marker, then time how long it takes for 10 complete rotations. By changing the hanging mass, you alter the centripetal force whilst measuring the period of rotation.
The analysis involves calculating T (period), v (linear velocity), and F (centripetal force) for each trial. When you plot F against v², you should get a straight line through the origin - this proves the F = mv²/r relationship.
Pro tip: This experiment beautifully demonstrates how increasing the centripetal force makes the object move faster in the same circular path!
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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.
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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.
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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
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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 😍😁😲🤑💗✨🎀😮
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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
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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
Comprehensive Circular Motion Notes for A-Level Physics
Yasmina Taleb Medarova
@yasminatalebmedarova_ipfc
Ever wondered why you feel pushed outwards when going around a sharp corner in a car? That's uniform circular motion in action! This topic explores how objects move in circles and the forces involved.
Understanding Radians and Circular Motion
Here's something that'll make angles much clearer: radians are simply the angle you get when the arc length equals the radius. Think of it like wrapping the radius around the circle's edge.
The key formula is θ = S/r, where θ is the angle in radians, S is the arc length, and r is the radius. For one complete revolution, you always get 2π radians (roughly 6.28), which equals 360 degrees.
Converting between radians and degrees is straightforward: multiply radians by 180/π to get degrees, or multiply degrees by π/180 to get radians. You'll use this constantly in physics calculations.
Quick tip: Remember that even though an object moves at constant speed in circular motion, its velocity constantly changes direction, which means it's always accelerating!
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Key Equations for Circular Motion
The maths behind circular motion involves four crucial quantities that work together beautifully. Linear velocity (v) measures how fast the object moves along the circular path, calculated as v = 2πr/T or v = 2πfr.
Angular velocity (ω) tells you how quickly the angle changes, using ω = 2π/T = 2πf. The brilliant connection between linear and angular velocity is simply v = ωr.
Centripetal acceleration always points towards the centre and equals a = v²/r = ω²r. This acceleration needs a force to maintain it - the centripetal force F = mv²/r = mω²r.
Remember: Centripetal force isn't a new type of force - it's just whatever force (tension, friction, gravity) that keeps the object moving in a circle!
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Investigating Circular Motion Practically
Want to see circular motion in action? The classic experiment involves whirling a bung (rubber stopper) attached to string through a tube, with weights hanging from the other end.
You keep the radius constant using a paperclip marker, then time how long it takes for 10 complete rotations. By changing the hanging mass, you alter the centripetal force whilst measuring the period of rotation.
The analysis involves calculating T (period), v (linear velocity), and F (centripetal force) for each trial. When you plot F against v², you should get a straight line through the origin - this proves the F = mv²/r relationship.
Pro tip: This experiment beautifully demonstrates how increasing the centripetal force makes the object move faster in the same circular path!
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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