# Basics: Electric Potential for a Point Charge

Pre Reqs: electric potential, electric field, work-energy To start, remember that for a constant electric field the change in electric potential energy would be: WARNING: that is only for a constant electric field. I know you will be tempted later to use this for a different electric field, but DON’T DO IT. But if not…

# Basics: Electric Potential

Pre Reqs: Electric Field, Work-Energy, Potential Energy If you are already familiar with the topics listed in the pre-reqs above, this will be uber-simple. Potential energy – short version The work-energy principle basically says: In this most basic form, the energy is just kinetic energy (if you are not going near the speed of light).…

# Basics: The electric field

Suppose I take a 1 kg ball and hold it near the surface of the Earth. What would be the gravitational force the Earth exerts on this ball? And I could say “g” is: The magnitude of this force would then be 9.8 Newtons. And, if I replaced the ball with a 10 kg ball,…

# Why are sparks blue?

I am not sure if First Excited State posted this as a blog entry, but it was mentioned on twitter. Question: why are sparks blue? My first gut response was that this is the blackbody color. Wrong for several reasons. The short answer is that sparks are blue because of the colors given off from…