Wait for it… wait for it… wait… for…… it……. GO!
Potential energy is *waiting* — it is stored up and ready to go. Once the energy is in motion, it becomes KINETIC energy!
♦ Potential energy is stored energy.
♦ Kinetic energy is in energy in motion.
Potential energy will continue to be stored until there is a change that causes that energy to be released. Let’s experiment with potential and kinetic energy!
- marble(s) – different sizes
- Ruler with a groove down the middle to act as a ramp
- Bottom of a carton container (milk, juice, something similar)
- Also a piece of paper taped to the table and folded up to act as a stopper would work as well.
- Books to give your “ramp” height
- Put the carton open mouth side towards the ruler (ramp)
- Put one skinny book under the other end or your ramp
- Roll a small marble down the ramp, does it move the carton or paper?
- Try it again with the ramp a little higher giving it more potential energy. What happens now?
Potential energy is the energy that an object has to be ABLE to DO something. Stored energy. The higher you raise the ramp, the further away from the table the marble is. Gravity is pulling on the marble the whole time and the further away from the table or ground it gets the more potential energy is being put into by you raising it higher and higher on the ramp allowing it to push the box, or the paper using the kinetic energy, which is energy that is being used.
- Canned goods of various sizes
- A lump of clay
- Newspaper or a tray – something to protect your surface area from falling cans
- Yardstick – optional
- Protect your surface area with the newspaper or tray
- Place a ball of clay on that protected surface
- Decide how high you want to drop your cans from onto your lump of clay.
- Use the ruler (or some other indicator – a large spoon, a stack of books, your little brother) to make sure that you are dropping the cans from the same height each time.
- Drop each can of differing weights onto the same lump of clay, remolding it into a ball each time to see the difference.
- Does the weight of the can affect the force that it exerts on the clay?
In this experiment, instead of things falling from different heights, the items falling are different weights falling from the same height. Did that affect the clay differently? Potential energy is stored energy, like when you pull your foot back to kick a ball or pull your arm back to throw a ball, or raise your hand to strum a guitar or just picking up your foot to take a step. Without putting much potential energy into the initial movement, there isn’t much kinetic energy as a result.