Newton’s Laws
Newton’s Second Law
The net force acting on a body is equal to the body's mass times its acceleration.
F=ma
From a mathematical standpoint this law is the most important one because this equation leads to the other equations of motion. It is important to remember here that forces are vectors and therefore have directions. If more than one force acts on a body it is the combined force that determines the body's motion.
Example: If you push a box with a force of 2N in the x-direction and the box has a mass of 2kg, what is the box's acceleration?
Answer: a=F/m Therefore a=2/2 = 1m/s2
Example: If you push the same box with a force of 4N in the x-direction and someone else pushes with a force of 2N in the minus x-direction what way will the box's acceleration be?
Answer: a= F/m, a=(4 + -2)/2 = 1m/s2 in the x-direction.