Question by : Help with science (physics) about energy?
homework. i need to know:
what is energy? how do you know when there is energy? and what we use it for.
it’s like fossil fuels, renewable energy, not body energy. unless it’s the same thing. D: and i know we use it for gas and electricity for homes and businesses. all i’ve found for what is energy is that it helps us do things, but that’s too basic.
i’m 14, year 10, make it half simple please?

There are two things in our world, one of which is energy and the other is mass. Energy is the flame on a candle and mass is the candle.

Give your answer to this question below!

### 2 Responses to “Help with science (physics) about energy?”

1. Everything is energy, but the study of how it is used in to produce fuel is called Thermodynamics. Here is a link to get you started.
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookEner1.html

2. If you are talking about energy in a physics class, then yes, it is all the same thing. By definition fuels contain energy…

Simply put, energy is the capability to perform work. There all multiple kinds of energy, from potential to kinetic. Energy can never be gained or lost, but can be transferred from one body to another through heat, light, and sound, among other things.

Take, for instance, a car crash where a car hits a tree. The car, traveling at 55 MPH, has a certain amount of energy. When it suddenly stops by striking the tree, that energy is transferred out of the movement of the car (meaning it stops) and transferred into the bending of the car parts, the sound of the crash, the damage to the tree, etc. The car got up to 55 in the first place by transferring the potential energy in the fuel into kinetic, heat and light energy in the combustion engine of the car.

Another example is holding a bowling ball over the side of the building. Gravity is exerting a downward force on the ball. You are exerting an equal force to hold it up (thank Isaac Newton by the way). The ball has the potential to accelerate at 9.8 m/s/s until it hits the ground, so it has potential energy at that point. Once you release the ball, it is now in motion, so the energy becomes kinetic, until it hits the ground, making a sound and probably a dent in something, transferring that energy out of the ball.

Clear as mud, right?