Capillary action would be most effective in which type of tube?

Capillary action is the ability of a liquid to flow in narrow spaces without the assistance of external forces, which is primarily driven by cohesive and adhesive forces. In a narrow tube, the surface tension of the liquid creates a strong interaction with the tube's walls due to adhesion, allowing the liquid to climb higher against the force of gravity.

When considering the height of the liquid column that can be achieved, taller tubes enhance the effects of capillary action because the adhesive forces can overcome the gravitational pull on the liquid for a greater vertical distance. Therefore, a narrow and tall tube maximizes the height of the liquid due to strong adhesive interactions with the walls of the tube while maintaining sufficient capillary pull.

In contrast, wider tubes exhibit reduced capillary action because the ratio of the adhesive surface area to the volume of the liquid is lower, diminishing the overall effect of the forces involved. Short tubes, regardless of width, limit the height to which the liquid can rise, counteracting the effect of the narrow width. Hence, a combination of being both narrow and tall allows for the most effective capillary action.