Which types of tachometers are available on the market?

Tachometers are essential tools used to measure the rotational speed of an engine, and they come in several types to accommodate different applications and preferences. The correct answer identifies the various types available, which include DC, AC, mechanical, analog, and digital tachometers.

DC tachometers operate on direct current electrical principles, providing accurate speed readings primarily in electrical systems. AC tachometers, on the other hand, function using alternating current, often preferred for applications requiring a robust performance against noise and interference.

Mechanical tachometers are driven by a flexible cable connected to the engine and utilize centrifugal forces to provide the speed readings, which are displayed on an analog dial. Analog tachometers provide continuous measurements that can be easily read, while digital tachometers display readings on an electronic screen, allowing for precise and easy interpretation.

This comprehensive approach ensures that users can select a type that best meets their specific needs in various engine setups and applications, making option C the most accurate representation of the market offerings.