This time we discuss the force required at the time of opening and closing the moving half mold after an injection mold has been installed in the injection molding machine. (See Fig. 1.)

Force is required to move an object. Force can be calculated using one of the famous Newton's laws of motion.

The point that should be noted here is that a is "acceleration" and not "velocity".
According to Newton's laws of motion:
1.Force is proportional to the mass.
2.Force is proportional to the acceleration.

Therefore, the force acting at the time of opening or closing a mold can be said to be proportional to the mass on the movable side and the acceleration.