Final answer:
Stationary radar uses microwaves and the Doppler effect to track the speed and distance of objects. By emitting microwaves and analyzing the frequency shift of returned echoes, a radar system can determine the motion attributes of various targets.
Step-by-step explanation:
Elements involved in completing a tracking history in stationary radar include various concepts from physics, specifically related to electromagnetic waves, their interaction with objects, and the analysis of these interactions to deduce information such as speed and distance. Radar systems use microwaves for detecting and timing the echoes returned from objects to determine their distance. When an object moves towards or away from the radar, the frequency of the returning microwaves is shifted, known as the Doppler effect. This effect allows the radar to measure the speed of the object.
For instance, police radar employs a Doppler-shift technique similar to that used in medical diagnostics to determine the speed of motor vehicles. The radar emits microwaves and then analyses the frequency of the return signal, which changes based on whether the object is moving towards or away from the radar. This change in frequency creates what is known as beats when mixed with the original frequency. In astronomy, radar is also used to measure the distances to planets and the speed of other objects within the solar system, by determining the Doppler shift in the radio waves reflected back.