Each of these lowers the force of the crash: objects that give way absorb energy, a stationary object adds no speed of its own, and a glancing blow transfers less force than a head-on hit. If a collision is likely, brake hard and steer toward the least harmful option.
Total stopping distance is the ground you cover while reacting plus the distance needed to brake, which depends on speed, brakes, tires, and the road surface. Darkness can make hazards harder to spot, but the clock itself does not change how far the vehicle needs to stop.
Tip When judging how quickly you can stop, think about speed, reaction time, brakes, tires, and pavement, not the hour.
Highway traffic moves fast, so situations change in seconds. Paying full attention, scanning constantly, and being ready for hazards such as debris, stalled cars, or sudden braking all help you avoid a crash.
A school bus stopped with its red lights flashing is letting children on or off, and they may walk across in front of traffic. You must halt at least 25 feet away and stay there until the red lights turn off and the stop arm retracts.
When wipers quit during rain or snow, your view is nearly gone. Slow down, and if looking out the open driver's window is your only means of seeing ahead, do so; brake and leave the road at the first safe chance. Once stopped, put on your hazard flashers and wait until the weather clears or the wipers are repaired.
Headlights are required from half an hour after sunset until half an hour before sunrise, plus whenever rain, fog, snow, or dim light makes people and vehicles hard to see. They help you see the road and help others see you.
Passing must always be done on the paved, main part of the road. Pulling onto the shoulder or dirt edge to get by is never allowed, even next to a vehicle that is turning left.
A stop sign, a red signal, and a stop order from an officer directing traffic each require a full stop. The same duty applies in other cases too, such as a school bus with flashing red lights or a train approaching a railroad crossing.
Cutting across a parking lot, gas station, or other property to avoid a sign or signal is illegal. The only exception is when a police officer directs traffic that way.
Tight or curving roads, intersections, railroad crossings, and wet or slippery pavement all leave less room for error. A lower speed buys you reaction time and cuts the distance you need to stop.
Most states require a parallel-parked car to have its wheels within 12 inches of the curb, and some allow up to 18, so staying within 12 inches keeps you legal in either case. A wider gap leaves the car sticking out into the travel lane, where it becomes a hazard to passing traffic.
Tip A gap of roughly 6 to 12 inches keeps you within the limit while protecting your tires from the curb.
A siren or flashing red or blue lights mean an emergency vehicle needs the road. Move to the right edge, stop, and stay there until it has gone by; failing to do so breaks the law and puts lives at risk.
Every question in this set has its own page with the correct answer and an explanation.
