Final answer:
The effect that is proportional to the size of the inversion pertains to the relationship between the speed of air through a radius and the square of that radius. As the radius decreases, the speed increases significantly, enabling actions such as blowing out a candle from afar by pursing one's lips.
Step-by-step explanation:
When we discuss inversely proportional relationships in physics, we are referring to a situation where one variable increases as another variable decreases. For instance, when considering the speed of air through a tube and its radius, we find that the speed is inversely proportional to the square of the radius of the tube. This creates large effects on the observed outcome when the radius changes. For example, by pursing your lips and decreasing the radius through which air is expelled, you can blow out a candle from a significant distance. This contrast dramatically with attempting the same action with your mouth wide open, where the large radius makes it quite ineffective. This principle is also reflected in other physical phenomena such as gravity and light propagation, where forces and brightness follow an inverse square law in relation to distance or separation.