What component provides engine RPM readings in a Cessna 172?

The tachometer is the component that provides engine RPM readings in a Cessna 172. It measures the rotational speed of the engine's crankshaft, providing pilots with critical information regarding the engine's performance during different phases of flight. Monitoring engine RPM is essential for ensuring the engine operates within safe limits and for optimizing performance, such as during climb, cruise, and approach.

The airspeed indicator displays the aircraft's speed through the air, which is distinct from engine RPM and does not provide information about the engine's performance. The manometer is not a typical instrument in the cockpit; it usually measures fluid pressure and is not related to engine speed. The Cylinder Head Temperature (CHT) gauge measures the temperature of the engine's cylinders, which is important for engine health, but it does not indicate engine RPM. Hence, the tachometer is the sole instrument dedicated to providing accurate RPM readings for the engine.