Final answer:
Motor oils are ranked based on their viscosity by observing how a sphere falls through them; the slower the fall, the higher the viscosity. Similarly, capillary action causes liquids to rise in tubes based on properties such as surface tension and tube radius, affecting the liquid's height.
Step-by-step explanation:
To rank the motor oils in order of increasing viscosity, we need to consider the time it takes for the spheres to fall through the oils. The greater the viscosity, the more resistant the fluid is to flow, and thus, the slower the sphere will fall. If the heights of the spheres (h1 to h4) after a brief moment are given, with h4 being the highest and h1 being the lowest, then the oil in tube 4 has the highest viscosity and the oil in tube 1 has the lowest viscosity.
In the context of capillary action, where liquids rise in tubes due to the balance between cohesive forces of the liquid and the adhesive forces between the liquid and tube, the capillary action can be described by the formula 2T cos 0 h = rpg, where h represents the height of the liquid column and corresponds to the water rising in a glass tube with a contact angle of 0°, indicating full spreading due to strong attraction.
Therefore, when comparing the liquid heights in tubes given the same conditions, such as airflow or introducing another liquid with a different density, you can determine the characteristics of the fluid, such as its viscosity or the capillary rise due to properties like surface tension and tube radius.