Force Part 4

Gravity is an example of force. Earth’s gravity pulls all objects toward its center. Friction is a force that holds back or slows down the motion of a sliding object. Balanced forces are equal in size, do not cause a change in motion, and act in opposite directions. When an unbalanced force acts on an object, it produces acceleration of the object, making it move or changing its motion. Newton’s first law of motion states that no acceleration can happen without an unbalanced force. Newton’s second law of motion states that an object’s acceleration depends on two factors: the amount of force applied to the object, and the object’s mass. Force = mass x acceleration Newton’s third law of motion states that whenever an object applies a force to a second object, the second object applies an equal and opposite force to the first object.