Subjects
Biology
Chemistry
AP Chemistry
English
AP English Literature
AP Environmental Science
Nov 26, 2025
45
4 pages
kylie @kylie_ywwr
Energy is the capacity to do work and exists in many different forms. From the kinetic energy of... Show more
Energy comes in many forms that you encounter daily. Kinetic energy powers moving objects, while potential energy remains stored until released. Other important types include thermal, electrical, chemical, nuclear, and light energy.
When objects move, they create force, which we calculate as mass times acceleration . This force is measured in newtons. When force acts through a distance, we call that work or energy, measured in joules (J).
Power describes how quickly energy is used or produced, measured in watts . This explains why your phone charger might be rated at 20W, while a nuclear power plant generates an enormous 1 gigawatt (1 billion watts)!
💡 Energy context A modern nuclear plant produces 1 GW of power—enough to power about 750,000 homes simultaneously!
The laws of thermodynamics govern all energy systems. The First Law states that energy cannot be created or destroyed—only transformed between different forms. The Second Law reveals that each time energy changes form, some is lost as heat.
This is why energy efficiency is always less than 100%. When we calculate efficiency (output÷input), most systems average just 30-50%. The rest becomes waste heat! This fundamental limit explains why your phone gets warm while charging and why cars need cooling systems.
Energy sources fall into two main categories. Renewable energy (solar, wind, hydroelectric) can naturally replenish at rates comparable to usage. Non-renewable energy (fossil fuels like coal, oil, and natural gas) exists in fixed amounts that take millions of years to form.
🔑 Remember When calculating with efficiency, input is ALWAYS larger than output. To find input (fuel needed), divide by efficiency; to find output (energy produced), multiply by efficiency.
Oil remains the world's most used energy source despite growing environmental concerns. Crude oil is naturally occurring petroleum pumped from oil fields and refined into products from gasoline to plastics. Natural gas, primarily methane, offers a cleaner-burning alternative to oil.
Understanding how fossil fuels form and collect helps explain their limited availability. Oil and gas migrate from source rocks (like oil shale) into reservoir rocks (like sandstone). Because of density differences, natural gas rises above oil, which floats above any water in these underground formations.
Energy powers our daily activities in countless ways. Building heating systems might use natural gas furnaces, electric heat pumps, or passive solar designs. Water heating traditionally uses insulated tanks, but newer tankless systems heat water on demand, saving energy and reducing water waste.
💡 Energy density matters! Countries like the US, Canada, and Saudi Arabia use much more energy per person than most other nations, creating both economic advantages and environmental challenges.
Transportation consumes massive amounts of energy moving people and goods around the globe. While petroleum products (gasoline, diesel, jet fuel) dominate, alternatives are growing natural gas vehicles, biofuels, hydrogen fuel cells, and electric vehicles all offer different advantages.
Energy conservation means reducing demand through behavior changes, while energy efficiency means getting more output from the same input through better technology. Both approaches help address environmental and resource concerns.
Green building design represents efficiency in action. Features like thicker windows, strategic building orientation to capture sunlight, rooftop solar panels, and natural lighting can reduce a building's energy needs by up to 70%. This matters because commercial buildings consume about 20% of all energy produced.
🌟 Take action Small changes add up! Switching to LED bulbs, unplugging unused devices, and adjusting your thermostat by just a few degrees can significantly reduce your personal energy footprint.
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.
2
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
App 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
kylie
@kylie_ywwr
Energy is the capacity to do work and exists in many different forms. From the kinetic energy of moving objects to the chemical energy in food, energy transformations power our world. Understanding energy concepts helps explain everything from how your... Show more
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Energy comes in many forms that you encounter daily. Kinetic energy powers moving objects, while potential energy remains stored until released. Other important types include thermal, electrical, chemical, nuclear, and light energy.
When objects move, they create force, which we calculate as mass times acceleration . This force is measured in newtons. When force acts through a distance, we call that work or energy, measured in joules (J).
Power describes how quickly energy is used or produced, measured in watts . This explains why your phone charger might be rated at 20W, while a nuclear power plant generates an enormous 1 gigawatt (1 billion watts)!
💡 Energy context: A modern nuclear plant produces 1 GW of power—enough to power about 750,000 homes simultaneously!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
The laws of thermodynamics govern all energy systems. The First Law states that energy cannot be created or destroyed—only transformed between different forms. The Second Law reveals that each time energy changes form, some is lost as heat.
This is why energy efficiency is always less than 100%. When we calculate efficiency (output÷input), most systems average just 30-50%. The rest becomes waste heat! This fundamental limit explains why your phone gets warm while charging and why cars need cooling systems.
Energy sources fall into two main categories. Renewable energy (solar, wind, hydroelectric) can naturally replenish at rates comparable to usage. Non-renewable energy (fossil fuels like coal, oil, and natural gas) exists in fixed amounts that take millions of years to form.
🔑 Remember: When calculating with efficiency, input is ALWAYS larger than output. To find input (fuel needed), divide by efficiency; to find output (energy produced), multiply by efficiency.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Oil remains the world's most used energy source despite growing environmental concerns. Crude oil is naturally occurring petroleum pumped from oil fields and refined into products from gasoline to plastics. Natural gas, primarily methane, offers a cleaner-burning alternative to oil.
Understanding how fossil fuels form and collect helps explain their limited availability. Oil and gas migrate from source rocks (like oil shale) into reservoir rocks (like sandstone). Because of density differences, natural gas rises above oil, which floats above any water in these underground formations.
Energy powers our daily activities in countless ways. Building heating systems might use natural gas furnaces, electric heat pumps, or passive solar designs. Water heating traditionally uses insulated tanks, but newer tankless systems heat water on demand, saving energy and reducing water waste.
💡 Energy density matters! Countries like the US, Canada, and Saudi Arabia use much more energy per person than most other nations, creating both economic advantages and environmental challenges.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Transportation consumes massive amounts of energy moving people and goods around the globe. While petroleum products (gasoline, diesel, jet fuel) dominate, alternatives are growing: natural gas vehicles, biofuels, hydrogen fuel cells, and electric vehicles all offer different advantages.
Energy conservation means reducing demand through behavior changes, while energy efficiency means getting more output from the same input through better technology. Both approaches help address environmental and resource concerns.
Green building design represents efficiency in action. Features like thicker windows, strategic building orientation to capture sunlight, rooftop solar panels, and natural lighting can reduce a building's energy needs by up to 70%. This matters because commercial buildings consume about 20% of all energy produced.
🌟 Take action: Small changes add up! Switching to LED bulbs, unplugging unused devices, and adjusting your thermostat by just a few degrees can significantly reduce your personal energy footprint.
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.
2
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
App 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
