Expressed by the famous equation F = ma, this law quantifies how forces affect the motion of a mass. It forms the basis of dynamic analysis, allowing engineers to calculate exactly how much torque a motor needs to spin up a heavy rotor in a given time, or the impact force a bumper will experience during a crash.
Heard on the job
Run the numbers through Newton's second law to size the actuator for that 500-kilogram payload.
Related terms
Newton's first law
The principle that a body remains at rest or in uniform motion unless acted upon by a net external force.
Newton's third law
The principle that every action force generates an equal and opposite reaction force.
Kinetics
The branch of classical mechanics that analyzes how forces and torques cause motion in physical bodies.