Imagine an arrow is shot from a bow and by the time it hits an apple it is traveling with 10 Joules of kinetic energy (kinetic energy is the energy of motion). What’s meant by kinetic energy is that when it hits something, it can do that much work on whatever is hit.

[am4show have='p9;p58;' guest_error='Guest error message' user_error='User error message' ]

Soooo, back to the arrow... if the arrow hits that apple it can exert 10 Joules of energy on that apple. It takes about 1 Newton of force to move that apple so the arrow can move the apple 10 meters. One Joule equals one Newton x one meter so 10 Joules would equal one Newton x 10 meters.

It could also exert a force of 10 Newtons over one meter or any other mathematical calculation you’d like to play with there. (This, by the way, is completely hypothetical. With the apple example we are conveniently ignoring a bunch of stuff like the fact that the arrow would actually pierce the apple, and that there’s friction, heat, sound, and a variety of other forces and energies that would take place here.)
<

Click here to go to next lesson on Freefall Pennies.

[/am4show]