Newtons laws of motion?

wow .. I don't even know how to respond to the above answers, maybe they shouldn't be answering questions in the science and mathematics section. Anyway, since the ball is not moving, Newton's first law states that every body remains in a state of constant velocity unless acted upon by an external unbalanced force. This means that in the absence of a non-zero net force, the body remains at a constant velocity or AT REST. In this case, the ball is at rest meaning the gravitational force that is acting on the ball is equal in magnitude to the tension force, assuming that the string makes a 90 degree angle with the ceiling or wherever it is being hung. The second example is a combination of Newton's second and third law. His second law states that an object will accelerate in the direction of the net force. In this example, the net force is in the direction of the plane's motion and is supplied by the engine. Air resistance is at 180 degrees to the plane's motion. Nevertheless, the plane is accelerating (Fnet = ma). Newton's third law states that every action force has a reaction force equal in magnitude but opposite in direction. The propellers, push back on the air molecules and the air molecules will push back with a force equal in magnitude but opposite in direction. This basic concept is how helicopters work.