BALLOOOOOON!

So, while trick-or-treating at Ala Moana Mall this Saturday, my little brother got a balloon. And sadly, this made me think of physics. I then asked him if I could steal his balloon (of course he told me no) and finally settled for borrowing it for one picture.

Naturally, after one random haunted house in some people's garage (pretty impressive, yeah?)

and a couple of ours of trick-or-treating, I forgot to take a picture of it. when I did try to take a picture this morning... well, let's just say that regular balloons FAIL. We can pretend that it's still floating, right? :P It sort of is... with help.

Now I'm sort of tempted to see how many photos I can get my brother into somehow... and I just realized that he's wearing the shirt that says "If you think I'm scary, you should see my sister". Ummmmm....

Ok, so for the real physics.... The balloon is pulling up with a force since the helium in the flimsy rubber is lighter than the air. This force is the tension in the string. The tension is also equal to the force that my brother has to pull down with to keep the balloon from floating away plus the force of mg (mass of the balloon and string times gravity), since the balloon isn't exactly going anywhere. (At least you hope so.)

Another physics concept that I noticed about the balloon was the tension as my brother ran away and the balloon streamed behind him. He pulled on the string, causing tension in the string, and this tension caused the balloon to have x velocity.

Hope everyone had a fun Halloween!

~Kira