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Middle school physics - NGSS
Changes in energy
Review your understanding of changes in energy in this free article aligned to NGSS standards.
Key points:
- Energy can’t be created or destroyed. If one object loses energy, another object has to gain that energy.
- Energy can be converted into different forms. For instance, a hairdryer takes electrical energy and converts it into thermal energy.
- When an object’s motion changes, so does its energy. If a bicycle slows down, it loses kinetic energy. That kinetic energy will be converted into another form, such as thermal energy, or transferred to another object.
- When a force acts on an object the energy of that object changes. For instance, when you hit the brakes on a bike, you’re applying a force to the wheels. That force converts some of the kinetic energy into heat.
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- If energy can’t be created how does it form(9 votes)
- It can't be formed, according to the Law of Conservation of Energy.(3 votes)
- Does velocity matter in transfer of energy(9 votes)
- Yep! There is a formula for Kinetic energy that says KE = half of your mass times your velocity squared (1/2 m v^2). So if two rocks both transfer all their energy somewhere, and both have the same mass, but one of them has a much greater velocity, then the one with the greater velocity will transfer more energy! This makes sense if you think about how much of a splash you can make in a pond by throwing a rock much harder (more velocity) or much softer, for example.(1 vote)
- i like how math help the earth but not me.(8 votes)
- This comment section is way better, back in the biology section the comments section literally just turned into a censored, cuss-free version of reddit(6 votes)
- If water freezes and becomes ice, will it have the same weight as before? (i know that its different volume and mass, but how about weight) ? pls explain(5 votes)
- #Meow🤣, anyways yes, the water would have the same mass as the ice because no matter the form of anything it will always be the same mass or have the same mass.
Sorry I'm 17 Days late but Hope this helps! :)(3 votes)
- Energy transformation is when energy changes from one form to another – like in a hydroelectric dam that transforms the kinetic energy of water into electrical energy. While energy can be transferred or transformed, the total amount of energy does not change – this is called energy conservation.(5 votes)
- I like how in the biology and earth courses people ask genuine uneducated questions and then here everyone's just like... it's math...there is no joy in life...-_-
I think I'm more at home here!🤣(5 votes) - Why is there no video?! ><(5 votes)
- because you dont stan wooyoung(1 vote)
- I love seeing the teachers who incorporate roller coasters and field trips to amusement parks in the name of science and energy. Sign me up! Has Khan entertained putting some "At home labs" to demonstrate these lessons?(4 votes)
- if you have two of the same mass of a ball and one faster why would that be ^-^(4 votes)
- because though they have the same mass they have different speed(1 vote)