Which type of tachometer utilizes reflecting tape to measure the rotation of an object?

The digital photo tachometer is the correct answer because it uses a beam of light and a photo sensor to detect the reflections from a surface, such as reflecting tape, attached to a rotating object. When the rotating object moves, the tape reflects light back to the sensor, allowing the tachometer to calculate the speed of rotation based on the frequency of the reflections it receives. This method provides an accurate and non-contact means of measuring rotational speed.

In contrast, other types of tachometers operate differently. For example, the electronic tachometer (often referred to as a stroboscope) typically utilizes a strobe light to visually freeze the motion of a surface, allowing the observer to count rotations per minute indirectly, rather than using reflected light to measure speed. The centrifugal-type tachometer works based on the centrifugal force generated by a rotating mechanism, which is not reliant on reflective surfaces. The chronometric tachometer, on the other hand, uses mechanical principles to measure time and speed, usually through an analog mechanism, rather than a photo sensor and reflecting tape. Therefore, the digital photo tachometer is uniquely suited for the purpose of utilizing reflecting tape for its measurements.