Sparks!!!

Most recent answer: 10/22/2007

Q:
How do you make sparks?
- haras doski (age 11)
perth,w.a,australia
A:
Haras -

As a general rule, sparks like the one in this picture are made when electrical charges move through air. But how do you get charges to go through air? One way is if you put one kind of charge (like positive charge) on one side of where you want the spark to be and the other kind (like negative charge) on the other side. Opposite charges are attracted to each other, so they will jump through the air to get together.

Electrical charges moving through the air

This is what’s happening in the picture. A whole lot of one kind of charge is put on the large metal ball. When you have a bunch of the same kind of charge, they push apart from each other and try to get as far apart as they can. In order to do this, they would like to jump to the smaller ball which is connected the ground (which is a place all charges would like to get to since there are lots of both positive and negative charges already there). The charges jump through the air (making a spark), then go through the smaller ball to reach the ground. This is also how we get lightning (a really big spark). All of one type of charge builds up on the clouds, and it jumps through the air to get to the ground, where it can spread out.

-Tamara

(published on 10/22/2007)