GENERAL KNOWLEDGE

Detailed explanation-1: -stroboscope, instrument that provides intermittent illumination of a rotating or vibrating object in order to study the motion of the object or to determine its rotary speed or vibration frequency.

Detailed explanation-2: -When you vary the strobe frequency of the stroboscope gradually from high to low, the mark on the motor shaft will appear to be stationary at a certain flashing frequency. When you see just one mark on the motor shaft, the corresponding flashing frequency is the rotation speed of the motor.

Detailed explanation-3: -1. the apparent motion of a series of separate stimuli occurring in close consecutive order, as in motion pictures. 2. the apparent motionlessness or reverse motion of a moving object, such as a rotating fan, produced by illuminating it with a series of intermittent light flashes. Also called stroboscopic effect.