A car traveling at 50 mph requires approximately how many feet to come to a complete stop?

• A. 150 feet
• B. 300 feet
• C. 400 feet
• D. 229 feet

Answer: (D)

Stopping distance is made up of two parts: the distance your car travels while you notice a hazard and decide to brake (reaction distance), and the distance you travel while the brakes bring you to a stop (braking distance). At 50 mph, you cover about 75 feet every second. If your reaction time is around one second, the reaction distance is roughly 75 feet. The braking distance on dry pavement with good brakes and tires at that speed is typically around 150 to 180 feet. Add them together and you get roughly 225 to 260 feet. About 229 feet sits right in that practical range for standard dry-road conditions, making it the best estimate. The other numbers would either represent braking distance alone, or assume conditions that shorten or lengthen stopping distance beyond typical dry-road performance.