TachometerSouth Africa

Learn traffic rules with clear explanations and visual examples in our illustrated book, designed to make studying simple and engaging.


86. Tachometer

A tachometer is an instrument that shows the rotational speed of an engine or motor, usually measured in revolutions per minute (RPM). It is commonly displayed on the vehicle's instrument panel near the speedometer.

A tachometer helps the driver understand how fast the engine is rotating and can assist with selecting an appropriate gear in vehicles with a manual transmission. It measures engine speed rather than the vehicle's road speed.

Tachometer in a Mazda RX-8.
Wikimedia.org • メルビル • CC BY-SA
What is a tachometer?

A tachometer is an instrument that measures and displays the rotational speed of an engine or motor, usually in revolutions per minute.

What does RPM mean on a tachometer?

RPM means revolutions per minute and indicates how many complete rotations the engine's crankshaft makes in one minute.

Is a tachometer the same as a speedometer?

No. A tachometer shows engine rotational speed, while a speedometer shows the vehicle's road speed.

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