Subjects
Biology
Chemistry
AP Chemistry
English
AP English Literature
Physics
Dec 1, 2025
327
3 pages
Katie Kozok @katiekozok19
Heat transfer is everywhere around you - from your radiator warming your room to feeling the sun's warmth... Show more
Every single object around you is constantly emitting and absorbing thermal radiation - yes, even you! This invisible infrared radiation is how heat travels through empty space, which is why you can feel warmth from the sun even though there's a massive vacuum between Earth and our star.
The hotter something gets, the more infrared radiation it pumps out. Think of a toaster - you can feel the heat radiating from it before you even touch it. This happens because infrared is part of the electromagnetic spectrum, travelling as waves that don't need any material to move through.
Here's a handy trick for staying cool or warm dark, matt surfaces are brilliant at both soaking up and giving off heat radiation. That's why wearing black on a sunny day makes you sweat more. Meanwhile, light, shiny materials are rubbish at this - they reflect most radiation away, which is why emergency blankets are shiny silver.
Quick Tip Ever wondered why car radiators are often black? It's because dark colours emit heat more effectively, helping your engine cool down faster!
Conduction only happens in solids and it's basically a massive game of particle pass-the-parcel. When you heat one end of a metal spoon, the particles there start vibrating more vigorously. These energetic particles bash into their neighbours, passing on their kinetic energy like a domino effect through the material.
Metals are absolutely champion conductors because they have something special - free electrons. These tiny particles can zip around freely, carrying thermal energy much faster than just particle vibrations alone. That's why a metal doorhandle feels freezing cold in winter (it's rapidly conducting heat away from your warm hand).
Materials without free electrons, like wood or plastic, are poor conductors (good insulators). The heat has to rely purely on particle vibrations, which is much slower and less efficient.
Remember Conduction needs direct contact - no gaps allowed! Heat always flows from hot areas to cold areas, never the other way round.
Convection is heat transfer with a twist - the material itself actually moves around, creating flowing currents. When you heat particles in liquids or gases, they gain kinetic energy and spread out more, making that region less dense and causing it to rise.
Picture your radiator at home it heats the air nearby, which expands and rises to the ceiling. As this warm air moves up, cooler, denser air rushes in from the sides to replace it. When the warm air eventually cools down at the ceiling, it becomes denser again and sinks back down. This creates a convection current - a continuous loop of moving air.
This same process explains why beaches are always windy. During the day, land heats up faster than the sea, creating rising warm air over the land. Cooler air from over the sea rushes in to replace it, creating that lovely sea breeze that makes coastal areas so pleasant.
The key thing to remember is that particles are constantly pushing and pulling each other around as they expand and contract with temperature changes.
Beach Science The reason land heats up faster than water is because water has a much higher specific heat capacity - it takes way more energy to warm it up!
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
You can download the app in the Google Play Store and in the Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
9
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
momentum, impulse, conservation of momentum
PhysicsZoology Notes
PhysicsExplore the principles of electricity, including potential difference, resistance, and current flow in series and parallel circuits. This summary covers key concepts such as Ohm's law, the behavior of filament lamps, and the role of various circuit components. Ideal for students preparing for assessments in physics.
PhysicsExplore the types of energy resources, including renewable and non-renewable sources, their environmental impacts, and applications in transport and heating. This summary covers key concepts such as fossil fuels, biofuels, and sustainable energy solutions, providing a comprehensive understanding for students studying energy resources.
PhysicsExplore the key concepts of energy conservation and dissipation, including power, efficiency, and the relationship between force and extension in elastic materials. This summary covers essential terms and principles relevant to energy transfers in electrical appliances and the limitations of proportionality in force-extension graphs.
PhysicsExplore key concepts of energy resources, including renewable and non-renewable types, their uses, and environmental impacts. This summary covers essential terms like fossil fuels, biofuels, and nuclear energy, providing insights into energy generation methods and their implications for climate change.
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
Katie Kozok
@katiekozok19
Heat transfer is everywhere around you - from your radiator warming your room to feeling the sun's warmth on your face. Understanding how thermal energy moves through radiation, conduction, and convection will help you explain loads of everyday phenomena, 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
Every single object around you is constantly emitting and absorbing thermal radiation - yes, even you! This invisible infrared radiation is how heat travels through empty space, which is why you can feel warmth from the sun even though there's a massive vacuum between Earth and our star.
The hotter something gets, the more infrared radiation it pumps out. Think of a toaster - you can feel the heat radiating from it before you even touch it. This happens because infrared is part of the electromagnetic spectrum, travelling as waves that don't need any material to move through.
Here's a handy trick for staying cool or warm: dark, matt surfaces are brilliant at both soaking up and giving off heat radiation. That's why wearing black on a sunny day makes you sweat more. Meanwhile, light, shiny materials are rubbish at this - they reflect most radiation away, which is why emergency blankets are shiny silver.
Quick Tip: Ever wondered why car radiators are often black? It's because dark colours emit heat more effectively, helping your engine cool down faster!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Conduction only happens in solids and it's basically a massive game of particle pass-the-parcel. When you heat one end of a metal spoon, the particles there start vibrating more vigorously. These energetic particles bash into their neighbours, passing on their kinetic energy like a domino effect through the material.
Metals are absolutely champion conductors because they have something special - free electrons. These tiny particles can zip around freely, carrying thermal energy much faster than just particle vibrations alone. That's why a metal doorhandle feels freezing cold in winter (it's rapidly conducting heat away from your warm hand).
Materials without free electrons, like wood or plastic, are poor conductors (good insulators). The heat has to rely purely on particle vibrations, which is much slower and less efficient.
Remember: Conduction needs direct contact - no gaps allowed! Heat always flows from hot areas to cold areas, never the other way round.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Convection is heat transfer with a twist - the material itself actually moves around, creating flowing currents. When you heat particles in liquids or gases, they gain kinetic energy and spread out more, making that region less dense and causing it to rise.
Picture your radiator at home: it heats the air nearby, which expands and rises to the ceiling. As this warm air moves up, cooler, denser air rushes in from the sides to replace it. When the warm air eventually cools down at the ceiling, it becomes denser again and sinks back down. This creates a convection current - a continuous loop of moving air.
This same process explains why beaches are always windy. During the day, land heats up faster than the sea, creating rising warm air over the land. Cooler air from over the sea rushes in to replace it, creating that lovely sea breeze that makes coastal areas so pleasant.
The key thing to remember is that particles are constantly pushing and pulling each other around as they expand and contract with temperature changes.
Beach Science: The reason land heats up faster than water is because water has a much higher specific heat capacity - it takes way more energy to warm it up!
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
You can download the app in the Google Play Store and in the Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
9
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
momentum, impulse, conservation of momentum
PhysicsZoology Notes
PhysicsExplore the principles of electricity, including potential difference, resistance, and current flow in series and parallel circuits. This summary covers key concepts such as Ohm's law, the behavior of filament lamps, and the role of various circuit components. Ideal for students preparing for assessments in physics.
PhysicsExplore the types of energy resources, including renewable and non-renewable sources, their environmental impacts, and applications in transport and heating. This summary covers key concepts such as fossil fuels, biofuels, and sustainable energy solutions, providing a comprehensive understanding for students studying energy resources.
PhysicsExplore the key concepts of energy conservation and dissipation, including power, efficiency, and the relationship between force and extension in elastic materials. This summary covers essential terms and principles relevant to energy transfers in electrical appliances and the limitations of proportionality in force-extension graphs.
PhysicsExplore key concepts of energy resources, including renewable and non-renewable types, their uses, and environmental impacts. This summary covers essential terms like fossil fuels, biofuels, and nuclear energy, providing insights into energy generation methods and their implications for climate change.
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
