A force of gravitational attraction exists between earth and every other material body in the universe. But the force of attraction toward the sun is so much larger than any of the others that all...
Any unbalanced force, but there must be a force.
they must be touching
The weight of the crate is acting downward on the ground and the ground is exerting a force equal to the weight of the crate upward on the crate.
The correct answer is gravity