Updated: Jan 5, 2021
By: Seth Peleg
Hello! Today I will be teaching about potential and kinetic energy and how they interact with gravity. All around us, there is energy being stored and released, and most of the time we don’t even notice it. Whether it’s a roller coaster or a simple game of catch there is potential and kinetic energy at work. Together they do a lot more than you might think.
Potential energy is the energy that is stored and ready to be used. Every single object has potential energy if it’s not moving or at its peak of motion. Take a swing, for example, If you look at the swing but don’t get on it yet the swing has potential energy because it can be swung. When the swing is at the apex or the highest point, it has massive amounts of potential energy too. Another example of potential energy is books on a bookshelf. If you lay a book on its side it has potential energy because they are not moving. If you stack multiple books side to side they also have potential energy because if one falls over, toppling over the rest, all of its potential energy is turned into kinetic energy.
Kinetic energy is mass in motion. If an object is moving it has kinetic energy. When you're playing catch, the ball has kinetic energy. All of the saved-up potential energy is converted to make the ball move forward. Another example is if you drop your notebook. When it is safe in your hands it has potential energy but when your hand slips and the notebook falls it trunks all the potential energy quickly turned into kinetic energy. So If there is ever potential energy there will almost always be kinetic energy to follow it.
Potential and kinetic energy always works with gravity. If we go back to the swing example both energies interact with gravity. After the apex of the swing and all the potential energy is turned into kinetic energy. When the swing is at its lowest point it has the most amount of kinetic energy because it’s working with gravity which is pulling it down. But when you start going back up you start losing kinetic energy because the swing is moving against gravity. The only reason the swing does not stop completely is because of your energy moving the swing. Another example is a roller coaster. When you are going up a massive hill in preparation for a huge drop, gravity is pulling the coaster down that’s why there is normally a chain pulling it up, or else the coaster would not go up hills. When you’re on the very top of the mountain and starting to face downward, potential energy is at its highest. Lastly, when the roller coast rockets down the track, all the potential energy is turned into kinetic with gravity also pulling it down.
Although we might not realize it, many types of energy are all around us. No matter what you are doing there is always potential and kinetic energy. Always remember that potential energy is energy being saved up and kinetic energy uses that energy when mass is in motion. I hope this was helpful, thank you for reading!
Question one: What is potential energy
Energy that is stored and ready to be used
Mass in motion
A game of catch
Question two: What is an example of kinetic energy
A bowling ball rolling down a lane
Books sitting still on a bookshelf
A hanging swing
Blankets laying on a bed
Question three: What does potential and kinetic energy work with
Rolling on a hill