Which of the following is NOT a way to measure with radar?

• A. Stationary
• B. Moving Opposite
• C. Moving Same
• D. Moving Parallel

Answer: (D)

The correct answer is that moving parallel is not a standard method for measuring speed with radar. In radar technology for speed measurement, the primary methods include stationary mode, moving opposite, and moving same.

In stationary mode, the radar unit remains in a fixed position while it measures the speed of approaching or receding vehicles. Moving opposite refers to situations where the radar is in motion and is measuring speed of a vehicle that is coming toward it, while moving same involves measuring the speed of a vehicle that is traveling in the same direction as the radar.

Moving parallel, however, does not fit the conventional methods of measuring speed. Radar relies on relative motion to determine speed differences based on the Doppler effect, and parallel movement would not create a measurable change in the Doppler shift needed to calculate speed accurately. Thus, it is not a recognized measurement approach in radar usage for speed detection.