It depends on how big you want the ball to be. You can probably make a reasonable sized one with 100-200 rubber bands. One of the big bags you can find in an office supply store would probably be enough to start out with.
Making rubber bands costs less than two cents per piece depending on the brand. Many rubber bands can be produced in a very short period of time.
1 gram
When it's released, the rubber band delivers almost as much energy as you had to produce in order to stretch it. The little bit that's missing is the energy that caused the rubber band to get warm as you stretched it.
the price varies with make and model. Call an authorized Servicer to gain cost of part.
225 grams
No. You also need to know the properties of the rubber band - specifically, how much it stretches for every unit of force applied.
Making rubber bands costs less than two cents per piece depending on the brand. Many rubber bands can be produced in a very short period of time.
$21
it cost 35
It takes 17 cents to by one pound of rubber.
I did a test on this on my engineering. It went up to about 1003.75 grams, or about 2.21 lbs.
That depends how hard you pull it. For example, if you don't pull it at all, it has zero potential energy. It also depends on the characteristics of the rubber band.
I good playable electric guitar for a band will cost you 300+ dollars.