An angle grinder primarily operates how?

An angle grinder primarily operates by using a high-speed rotating disc or wheel that can cut, grind, and polish various materials including metal, wood, and masonry. The process involves the mechanical action of the rotating disc against the surface of the material, which generates heat through friction and can also create sparks. This action is not just limited to cleaning surfaces but is also effective for cutting and grinding.

While option B mentions the act of using friction to remove unwanted deposits and dirt, it does not fully capture the core functionality of an angle grinder, which is versatile in its capabilities. It is also important to note that angle grinders do indeed produce sparks during operation, especially when grinding or cutting metal—contradicting the claim in option D.

The other options either limit the grinder's application to specific tasks or misunderstand its operational fundamentals. Hence, recognizing that the angle grinder is a powerful tool designed for a wide range of tasks helps clarify its primary operation.