Force
In physics, a force is any interaction that, when unopposed, will change the motion of an object. A force can cause an object with mass to change its velocity (which includes to begin moving from a state of rest), i.e., to accelerate. Force can also be described intuitively as a push or a pull. A force has both magnitude and direction, making it a vector quantity. It is measured in the SI unit of newtons and represented by the symbol F.
Newton (unit)
Newton's second law of motion states that , where is the force applied, is the mass of the object receiving the force, and is the acceleration of the object. The newton is therefore:
where the following symbols are used for the units: N for newton, kg for kilogram, m for metre, and s for second.