What is Elastic Force?

Elastic force is a force (duh) that is created by an object that has changed shape but tries to go back to its old form. The best example of this is a rubber band, but it happens in other opbjects such as some springs, and others. For instance if you were trying to mave a cart with a rubber band there are two options you have. 1 to tie the rubber band to the cart and pull it (this way does use elastic force but not much) 2, to make a slingshot out of the rubber band and launch it (this way uses a lot of elastic force but cannot direct it much).

What is gravity?

gravity is a force that acts on objects to pull it twards large objects of mass, such as the moon, the sun, the eath, etc. it is what makes you have weight (the difference between mass and weight is that mass is the amount of stuff in an object and weight is how much gravity pulls it down.)