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.

Aman throws a football straight into the air. as it rises, it slows down. which type of energy is the football gaining?

If jerome is swinging on a rope and transferring energy from gravitational potential energy to kinetic energy, is being done.

Place several e-field sensors at a few points on different equipotential lines, and look at the relationship between the electric field and the equipotential lines. which statement is true? 1-at any point, the electric field is perpendicular to the equipotential line at that point, and it is directed toward lines of higher voltages. 2-at any point, the electric field is perpendicular to the equipotential line at that point, and it is directed toward lines of lower voltages. 3-at any point, the electric field is parallel to the equipotential line at that point.