North Carolina RADAR State Practice Exam

If the target speed is 70 mph and the patrol speed is 65 mph, what is the closing speed?

1. 135 mph

2. 5 mph

3. 65 mph

4. 70 mph

The correct answer is: 135 mph

The closing speed is calculated by determining the difference in speeds between the target vehicle and the patrol vehicle. In this scenario, the target speed is 70 mph, indicating how fast the vehicle being observed is moving, while the patrol speed is 65 mph, which is the speed at which the enforcement vehicle is traveling. To find the closing speed, you take the speed of the target and add it to the speed of the patrol vehicle when they are moving towards each other. When moving in the same direction, the closing speed is calculated by subtracting the patrol speed from the target speed. In this case, however, the most relevant factor is that the target vehicle is moving faster than the patrol vehicle. Thus, the closing speed would be 70 mph (the speed of the target vehicle) minus 65 mph (the speed of the patrol vehicle), resulting in a closing speed of 5 mph. Therefore, the correct interpretation here is that the closing speed between the vehicles, given that the target is speeding, would indicate the relative approach or distance contraction per unit of time, which helps law enforcement in gauging the situation and responding with appropriate measures. It appears there may be confusion in understanding the calculation; the closing speed in this example