How far should lawful brakes stop a car at 20 miles per hour, not including thinking distance?

The distance required for lawful brakes to stop a car traveling at 20 miles per hour is typically around 19 feet. This distance is based on various factors including the vehicle's braking system, road conditions, and tire grip.

At 20 miles per hour, the braking distance calculation can be influenced by physics, particularly the concept of kinetic energy and friction. When a car is moving, it possesses kinetic energy that needs to be dissipated when brakes are applied. The braking distance increases with the square of the speed, so while the stopping distance is relatively short at lower speeds, it becomes significant as speed increases.

In this scenario, the 19 feet represents a reasonable estimate for how far a car should travel after the brakes are engaged, providing a clear understanding of safe stopping distances. Meanwhile, the figures provided in the other options represent distances that do not accurately correspond to the established braking distances associated with that speed.