Water on a smooth floor can made you slip, which means water is also a lubricant. Can you think of reasons why oil and grease and not water is used i machines as a lubricant?
The boiling of water is 100°, while the boiling point of lubricating oil is anywhere from 370°-600°. So oil is used because if the machine gets too hot, then the water may boil off, which will make the machine lose its lubrication.
