Energy Stores and Transfers
Ever wonder why a moving car has more energy than a parked one? Energy stores are simply different ways that objects can hold energy, and there are several key types you need to know.
Kinetic energy is found in anything that's moving - your bike, a bouncing ball, or even tiny vibrating atoms. The faster something moves, the more kinetic energy it has. You can calculate this using the formula Ek = ½mv², where m is mass (in kg) and v is speed inm/s.
Gravitational potential energy (GPE) increases when you lift objects higher in Earth's gravitational field. Think about carrying your bag upstairs - you're doing work against gravity and storing energy. The formula Ep = mgh shows how GPE depends on mass (m), gravitational field strength (g), and height (h).
Other important energy stores include thermal (heat), elastic potential (stretched springs), chemical (food and batteries), magnetic, electrostatic, and nuclear. Energy transfers happen through mechanical work, electrical work, heating, or radiation.
Key Point: Work done always equals energy transferred - this is fundamental to solving energy problems!