Newton's Second Law of Motion states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.

This can be expressed mathematically as:

F = ma

Where:

* F is the net force acting on the object

* m is the mass of the object

* a is the acceleration of the object

This means that:

* A greater force is required to accelerate a heavier object at the same rate as a lighter object.

* A heavier object will accelerate slower than a lighter object if the same force is applied to both.

So, the heavier the object, the more force is required to move or accelerate it. This is why it takes more effort to push a heavy box than a light one.