Second law of motion

Newton’s second law of motion states:

The acceleration of an object is directly proportional to the net force acting on it, and inversely proportional to its mass.

What does this mean?

• If you apply a greater force to an object, it will accelerate more.
• If you apply the same force to a heavier object, it will accelerate less:
  • That’s because heavier objects need more force to accelerate them (because they have more inertia).

Equations

In short, Newton’s second law of motion can be written as:

\Sigma F = ma

Where:

• \Sigma F is the net (resultant) force acting on the object in newtons (N)
• m is the mass of the object in kilograms (kg)
• a is the acceleration of the object in meters per second squared (ms^{-2})