How does a VASCAR device work?

A VASCAR device, which stands for Visual Average Speed Computer And Recorder, operates by averaging the time taken for a vehicle to travel a predetermined distance. This approach involves the officer marking a start and endpoint on the road, typically using a calibrated visual reference in conjunction with the stopwatch feature. The VASCAR calculates the average speed by taking the distance between these two points and dividing it by the time it takes for the vehicle to travel that distance.

This method is particularly useful for measuring speeds in scenarios where traditional radar technology may not be as effective, such as on curved roads or when targeting multiple vehicles. The accuracy relies on the officer's ability to start and stop the timing accurately as the vehicle passes the markers. Therefore, the correct answer highlights the functionality of VASCAR effectively and reflects its reliance on time and distance for speed calculation.