For the following situations, describe the contact and non-contact forces that are involved.
- A book sitting on a shelf
- A soccer player kicking a ball; the ball soaring through the air and landing on the ground
- A hiker in the woods reading her compass to determine which direction to go
- A child on a sled; first, the child is sitting at the top of the hill, waiting his turn; then, the child pushes off and slides down the hill, eventually coming to a stop.
