What units are commonly used to express speed on radar displays?

Speed is typically expressed on radar displays in units that are most relevant and understandable for vehicular speeds. Miles per hour (mph) and kilometers per hour (kph) are the standard units used in many countries for measuring the speed of vehicles. This makes them particularly suitable for radar applications in law enforcement, where understanding and enforcing speed limits in a familiar context is necessary.

The use of mph and kph aligns with the conventional measurements seen on road signs and speedometers, facilitating quick comprehension for both operators and drivers. This clarity is critical in enforcing speed regulations effectively.

The other units mentioned, such as feet per second (fps) and meters per second (m/s), while valid measurements of speed, are less common for radar applications focused on cars, where mph and kph are more prevalent. Knots and leagues are not standard for vehicular speed measurements, with knots being primarily used in maritime and aviation contexts. Lastly, inches per hour and centimeters per hour represent very small increments of speed that are impractical for assessing vehicle speeds.