What instrument allows viewing of rotating or reciprocating objects intermittently to create the effect of slow motion?

The stroboscope is an instrument that emits short bursts of light at regular intervals, which allows for the observed motion of a rotating or reciprocating object to appear slowed down or even stationary. This effect occurs because the bursts of light illuminate the object at specific points in its motion, creating the illusion of slow motion. The timing of the strobe light can be adjusted, allowing operators to synchronize it with the speed of the rotating or reciprocating object, making it a valuable tool in fields such as mechanical engineering and photography where understanding motion is crucial.

In contrast, a cinematograph records and plays back moving images, capturing motion without the same instantaneous effect as a stroboscope. A projector displays film or images on a screen and also does not provide the intermittent viewing necessary for achieving the slow-motion effect. Similarly, a laser scanner is used for measuring distances or capturing images and does not have the same application for viewing motion in the way required.