Physics is all about how energy behaves in our world.... Show more
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
6
0
Scarlett Edwardes
12/6/2025
Physics
Energy
186
•
Dec 6, 2025
•
Exploring the Basics of Energy
Scarlett Edwardes
@scarlett_1917
1 / 6
Energy Stores and Transfers
Energy is one of the most fundamental concepts in physics that you'll use throughout your studies. The most important thing to remember is that energy is never created or destroyed—it simply changes form.
Energy exists in various stores including thermal (internal), kinetic, gravitational potential, elastic potential, chemical, magnetic, nuclear, and electrostatic. When energy moves from one store to another, we call this a transfer.
Energy transfers happen in four main ways: mechanically (through forces doing work), electronically (by moving charges), heating (work done by heat), and radiation (work done by light or sound).
Remember this! When energy moves from one store to another, physicists call this "work done." This concept will appear repeatedly in your exams.
Gravitational Potential Energy
When you lift an object upwards, you're transferring energy into its gravitational potential energy (GPE) store. The higher you lift it, the more energy is stored.
This happens because the object exists in Earth's gravitational field, and energy is needed to work against this force. The amount of GPE depends on three factors: the object's mass, its height, and the strength of the gravitational field.
We calculate changes in GPE using the formula: Ep = mgh where m is mass in kg, g is gravitational field strength in N/kg, and h is height in meters.
Quick fact: The gravitational field strength on Earth is approximately 10 N/kg. This value makes calculations in your exams much easier!
Kinetic Energy
Kinetic energy is the energy an object has due to its motion. Energy transfers into the kinetic store when an object speeds up and transfers away when it slows down.
The amount of energy in this store depends on both the object's mass and its speed, calculated using: Ek = ½mv² where m is mass in kg and v is speed in m/s. Notice that doubling the speed quadruples the kinetic energy!
When an object falls, energy transfers between gravitational potential energy and kinetic energy stores. With no air resistance, the energy lost from the GPE store equals the energy gained in the kinetic store—this is conservation of energy in action.
Important: In real-world situations, air resistance causes some energy to be transferred to the thermal store of the surroundings instead of just to kinetic energy. This is why falling objects reach a terminal velocity.
Elastic Potential Energy
Elastic potential energy is stored when you stretch or compress objects like springs. Think about pulling back a catapult or stretching a rubber band—you're storing energy!
As long as you don't stretch beyond the limit of proportionality (where the object's behavior changes), elastic potential energy can be calculated using: Ee = ½ke² where k is the spring constant in N/m and e is extension in m.
The spring constant tells us how stiff a spring is—a higher value means a stiffer spring that's harder to stretch but stores more energy for the same extension.
Key concept: The limit of proportionality marks where Hooke's Law stops working. Before this point, extension is directly proportional to the force applied. This relationship appears regularly in exam questions!
Thermal Energy and Specific Heat Capacity
Thermal energy (also called internal energy) is the total kinetic energy of all particles in an object. It's what we're really talking about when we discuss temperature—the more energetic the particles, the higher the temperature.
Different materials require different amounts of energy to heat up. Specific heat capacity measures how much energy (in joules) is needed to raise the temperature of 1kg of a substance by 1°C.
We calculate changes in thermal energy using: E = mc∆θ where E is energy in joules, m is mass in kg, c is specific heat capacity in J/kg°C, and ∆θ is the temperature change in °C.
Practical application: Materials with high specific heat capacity (like water) are excellent for storing thermal energy, which is why they're used in heating systems. This concept helps explain why coastal areas have milder climates than inland regions.
We thought you’d never ask...
What is the Knowunity AI companion?
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.
Where can I download the Knowunity app?
You can download the app in the Google Play Store and in the Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
4.9/5
App Store
4.8/5
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
Exploring the Basics of Energy
Scarlett Edwardes
@scarlett_1917
Physics is all about how energy behaves in our world. Energy never disappears but constantly moves between different stores through various transfer methods. Understanding these energy stores and their mathematical relationships is key to mastering many physics concepts.
Energy Stores and Transfers
Energy is one of the most fundamental concepts in physics that you'll use throughout your studies. The most important thing to remember is that energy is never created or destroyed—it simply changes form.
Energy exists in various stores including thermal (internal), kinetic, gravitational potential, elastic potential, chemical, magnetic, nuclear, and electrostatic. When energy moves from one store to another, we call this a transfer.
Energy transfers happen in four main ways: mechanically (through forces doing work), electronically (by moving charges), heating (work done by heat), and radiation (work done by light or sound).
Remember this! When energy moves from one store to another, physicists call this "work done." This concept will appear repeatedly in your exams.
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Gravitational Potential Energy
When you lift an object upwards, you're transferring energy into its gravitational potential energy (GPE) store. The higher you lift it, the more energy is stored.
This happens because the object exists in Earth's gravitational field, and energy is needed to work against this force. The amount of GPE depends on three factors: the object's mass, its height, and the strength of the gravitational field.
We calculate changes in GPE using the formula: Ep = mgh where m is mass in kg, g is gravitational field strength in N/kg, and h is height in meters.
Quick fact: The gravitational field strength on Earth is approximately 10 N/kg. This value makes calculations in your exams much easier!
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Kinetic Energy
Kinetic energy is the energy an object has due to its motion. Energy transfers into the kinetic store when an object speeds up and transfers away when it slows down.
The amount of energy in this store depends on both the object's mass and its speed, calculated using: Ek = ½mv² where m is mass in kg and v is speed in m/s. Notice that doubling the speed quadruples the kinetic energy!
When an object falls, energy transfers between gravitational potential energy and kinetic energy stores. With no air resistance, the energy lost from the GPE store equals the energy gained in the kinetic store—this is conservation of energy in action.
Important: In real-world situations, air resistance causes some energy to be transferred to the thermal store of the surroundings instead of just to kinetic energy. This is why falling objects reach a terminal velocity.
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Elastic Potential Energy
Elastic potential energy is stored when you stretch or compress objects like springs. Think about pulling back a catapult or stretching a rubber band—you're storing energy!
As long as you don't stretch beyond the limit of proportionality (where the object's behavior changes), elastic potential energy can be calculated using: Ee = ½ke² where k is the spring constant in N/m and e is extension in m.
The spring constant tells us how stiff a spring is—a higher value means a stiffer spring that's harder to stretch but stores more energy for the same extension.
Key concept: The limit of proportionality marks where Hooke's Law stops working. Before this point, extension is directly proportional to the force applied. This relationship appears regularly in exam questions!
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Thermal Energy and Specific Heat Capacity
Thermal energy (also called internal energy) is the total kinetic energy of all particles in an object. It's what we're really talking about when we discuss temperature—the more energetic the particles, the higher the temperature.
Different materials require different amounts of energy to heat up. Specific heat capacity measures how much energy (in joules) is needed to raise the temperature of 1kg of a substance by 1°C.
We calculate changes in thermal energy using: E = mc∆θ where E is energy in joules, m is mass in kg, c is specific heat capacity in J/kg°C, and ∆θ is the temperature change in °C.
Practical application: Materials with high specific heat capacity (like water) are excellent for storing thermal energy, which is why they're used in heating systems. This concept helps explain why coastal areas have milder climates than inland regions.
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
We thought you’d never ask...
What is the Knowunity AI companion?
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.
Where can I download the Knowunity app?
You can download the app in the Google Play Store and in the Apple App Store.
Is Knowunity really free of charge?
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
Mock Exam
Quiz
Flashcards
Essay
Similar Content
Power
Physics
PhysicsDigestive System & Nutrition Study Guide
here is a study guide to help you !
Physics11th
Physics Formula Sheet
This includes different formulas involved in physics subject.
Physics12th
Energy Conservation Principles
Explore 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.
Physics11
Zoology Unit 1
Zoology Notes
PhysicsPhysics Energy Concepts
Explore key concepts in physics related to energy, power, and electricity. This resource covers topics such as energy transfer, Ohm's Law, radioactivity, and thermal energy, providing a comprehensive overview for GCSE Triple Science revision. Ideal for students preparing for exams, this summary includes essential equations and principles to enhance understanding.
Physics11
Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
4.9/5
App Store
4.8/5
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