When should a vehicle equipped with brakes be able to stop under ideal conditions?

• A. Within 20 feet
• B. Within 40 feet
• C. Within 60 feet
• D. Within 80 feet

Answer: (B)

The main idea here is braking distance: how far you travel after you start braking under ideal, dry-road conditions. Under those good conditions, a typical vehicle with functioning brakes can come to a complete stop in about 40 feet after the brakes are applied. This 40-foot figure is a standard benchmark used in Texas Class B prep to represent safe braking distance in normal city-speed driving.

Twenty feet would be unrealistically short for most cars to stop safely after braking starts, even on dry pavement. Sixty or eighty feet imply longer stopping distances that would occur at higher speeds or with poor conditions, not the ideal scenario described here. So, 40 feet is the appropriate, conservative braking distance under ideal conditions.