Here's why:

* Newton's First Law of Motion (Inertia): This law states that an object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. This law doesn't directly involve mass or acceleration.

* Newton's Second Law of Motion: This law states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. This is mathematically expressed as:

F = m * a

Where:

* F = Force (measured in Newtons)

* m = Mass (measured in kilograms)

* a = Acceleration (measured in meters per second squared)

In essence, the calculation mass x acceleration gives you the net force acting on an object.