Does a skydiver falling from an altitude of 1.5 km have a force ballanced or unballanced?

By definition, if he is accelerating, then it is an unbalanced force ... which means he JUST jumped out the plane and his downward speed in increasing. Once he reaches a particular speed (called terminal velocity; lets call it for a general case of about 110 mph), the force of DRAG will be equal to the force due to gravity and he will no longer be accelerating, no longer increasing in speed, and he will then have balanced forces.

Since the variables are always changing, drag will change with the most subtle changes in the skydiver's orientation either intentionally or unintentionally and the air resistance is constantly changing with increase in density, the forces will never be truly balanced. The effect of both forces will seesaw between one or the other being dominant. Terminal velocity is achieved when that process is minimal.

It is of note that the effect of gravity itself is changing but over a skydive, the effect is negligible and may be ignored.