Final answer:
The two factors that control the selection of oil or grease for a bearing application are rotational speed and load.
Step-by-step explanation:
The two factors that control the selection of oil or grease for a bearing application are rotational speed and load.
Load refers to the weight or force applied to the bearing, and it determines the pressure on the lubricant between the bearing surfaces. Higher loads require a lubricant with greater viscosity to maintain a sufficient lubricating film.
For example, in high-speed applications with heavy loads, such as automotive engines, the oil used needs to have a higher viscosity to ensure proper lubrication and minimize friction and wear.