Texas DPS Class C Road Rules Practice Test

To understand the stopping distance at 20 mph, it's important to consider both the distance covered while reacting to a situation and the distance required to physically stop the vehicle.

At 20 mph, the average driver's reaction time, which is typically about 1.5 seconds, means that the vehicle continues to travel forward at that speed during the time it takes for the driver to perceive the need to stop and then act on that decision.

Using the formula for the stopping distance, which includes both the thinking distance (the distance traveled during reaction time) and the braking distance (the distance it takes to stop once the brakes are applied), we can calculate the total stopping distance.

At 20 mph, a vehicle travels approximately 29.3 feet per second. Therefore, during the 1.5 seconds of reaction time, the vehicle would cover about 44 feet (29.3 feet/second x 1.5 seconds). The braking distance at 20 mph typically adds another 19 feet. Adding these two components together gives a total stopping distance of approximately 63 feet.

Thus, the response stating that the stopping distance at 20 mph is 63 feet incorporates the crucial elements of reaction time and braking distance together, which aligns with standard