Henry sets his keys on a wooden table.

He then takes a powerful magnet and positions it below the table and the keys. He finds that he is able to drag the keys along the table by moving the magnet. This demonstrates that
A.
magnetic forces act on wooden objects.
B.
magnetic forces act at a distance.
C.
gravitational forces are contact forces.
D.
gravity is proportional to mass.

Apossible explanation for a set of facts that can be tested by further investigation is called

When you jump from an elevated position you usually bend your knees upon reaching the ground. by doing this, you make the time of the impact about 10 times as great as for a stiff-legged landing. in this way the average force your body experiences is a) less than 1/10 as great. b) more than 1/10 as great. c) about 1/10 as great.d) about 10 times as great.

A250-n box is at rest on a frictionless horizotal floor. then a person shoves the box with a non-zero force of magnitude p. which statement best describes the relationship betweeen p and the motion of the box after it was shoved? -the box will not move when p< 250n but otherwise will accelerate at a constant rate that is directly proportional to p - the box will begin moving at a speed that is directly proportional to p, then will gradually slow to a halt -the box will move with constant velocity at a speed that is directly proportional to p -box will accelerate across the floor at a constant rate that is directly proportional to p