GGRAVITY – The force that pulls all objects towards the center of the earth. CCENTER OF GRAVITY – The point around an object where all of its weight is balanced evenly.
GOING UPHILL - The car slows down. Maintain the speed limit. Slow at the top of the hill. tay to the right side of your lane. Braking distance shortens
GOING DOWNHILL –The car speeds up. Ease off gas. Pump your brakes to slow. Don’t ride the brakes. Downshift to a lower gear. Braking distance lengthens.
Kinetic energy is the energy an object has as a result of its moving. A vehicles energy of motion doubles when its weight doubles. Now the vehicle needs twice the distance to stop.
A vehicles energy of motion is proportional to the square of its increase in speed. When speed doubles, the vehicle needs about 4 times the distance to stop. When speed triples, it needs about 9 times the distance to stop.
Energy that is moving has to be changed to heat by what we call friction in order to stop a moving car. As you increase speed, you also increase the cars momentum. To stop, you need more friction or a longer stopping distance.
Resistance of two objects which are moving against each other. Control of a car depends on the friction. When friction is reduced, you have less control over your car. 3 sources of friction are used to stop a moving car. 1. Tires gripping the road surface. 2. The brakes working properly. 3. The road surface itself.
1.Snow 2. Ice 3. Water 4. Gravel 5. Sand 6. Tires 7. Wet leaves 8. Mud
Tires actually control the movement of a vehicle. Tread – The grooved surface of a tire that grips the road. When the road is wet, the tread allows water to flow through the grooves and away from the tire.
Bald tire – A tire with little or no tread. The tire won’t be able to grip a wet or icy road. Blowout – A sudden loss of tire pressure.
Underinflation – Only the outside edges of the tire grip the road. This will make the outside edges of the tire wear quickly. Overinflation – Only the center of the tire grips the road. Therefore the center of the tire will wear more quickly. Proper Inflation – All of the weight of the tire to the road is equally distributed. More of the tire is gripping the road. This will give you better traction.
When the temperature outside increases, tire pressure also increases. When the weather turns colder, tire pressure decreases.
1.Good car condition * Shock Absorbers * Steering System * Tires 2. Good Roadway Surfaces * paved * clean * dry * level
Wet roads on bridges and overpasses or in shaded areas will freeze before other road surfaces as the temperature nears freezing. Brake gently to check traction and see how your vehicle responds.
Factors that affect the control you have over your vehicle in a curve. 1. Speed. 2. Sharpness of the curve. 3. Bank of a curve. 4. Load.
Energy of motion tries to keep a car going in a straight line. You must slow down to reduce the energy of motion when going around a curve. All roads are crowned. This means the center of the road is higher than the sides. This is for drainage of water.
The distance your vehicle takes to stop. This distance is measured from the point you first see a problem to the point where your vehicle stops. Total Stopping Distance
PERCEPTION TIME – The length of time it takes you to identify a situation. PERCEPTION DISTANCE – The distance your vehicle travels during this time.
1. Visibility. 2. Condition of the driver. 3. Your ability to recognize the hazard.
REACTION TIME – Once you have identified a hazard, the length of time you take to react. REACTION DISTANCE – The distance a car travels during this time. Average driver’s reaction time – ¾ of a second.
The distance your car travels from the time you apply the brakes until your car stops.
1.Speed4. Driver Reaction 2.Car Condition 5. Hills 3.Road Surface6. Load
1. ACTIVE – You have to put them on yourself. 2. PASSIVE – When the protection is already provided. Automatic seat belts and air bags.
The force which is generated when one moving object collides with another object. Factors affecting impact: 1. Speed. 2. Weight. 3. Distance between impact and stop. When your speed doubles, impact becomes 4X greater. When it triples, it becomes 9X greater.
COLLISIONS It is safer to stay in the car during the collision. Most collisions occur at speeds less than 40 mph. There are two collisions when a car hits a solid object. Car to object Passengers to seat belt, steering wheel, wind shield, or other seat.
REDUCED VISIBILITY REDUCED VISIBILITY 1. Car windows steamed up * Defroster, rear defog * Open Window * Vent, air conditioner, heater
2. SNOW, ICE, or FROST on Windows * Clear windows BEFORE driving. * Use defroster to keep clear. 3. DIRTY WINDOWS * Bugs * Smoke * Keep your windows clean.
4. GLARE FROM THE SUN It is worse in the early morning or late afternoon. Keep your windows clean Wear sunglasses Use the sun visor 5. Dawn and Dusk Driving * Use your headlights to make yourself more visible to other drivers and roadway users.
6. NIGHT TIME DRIVING Don’t overdrive your headlights Use high beams when there are no vehicles ahead of you. Switch to low beams as soon as you see an oncoming vehicles headlights or the taillights of a vehicle you are following. Use low beams during adverse weather at night. (Rain, snow, or fog) High beams causes more light to reflect back into your eyes.
1. Choose a fixed object ahead of your car at the time the object appears within your lighted area. 2. Start counting, if you reach the object after 4 seconds your speed is correct. If you reach it before 4 seconds, you need to slow down.
Briefly flick on your high beams to remind the oncoming driver to switch to his low beams. If this doesn’t work, slow down and glance to the right of the road. Do not look directly at the bright lights and do not leave yours on.
WET ROADS – Roads are slickest just after it starts to rain, because oil and dirt is brought to the surface. When it rains, the road is drier where the car ahead of you has left tracks. Drive in the tracks for better traction.
When the tires of a moving vehicle ride on the surface of water, causing loss of steering and braking control. To avoid hydroplaning, reduce speed and use properly inflated tires with good tread. Pump your brakes after driving through deep water.
* Initial snow is better than packed snow for traction. Packed snow is like ice. * Roads are extremely slick when the temperature nears freezing.
Gentle actions are the key. Don’t do anything sudden. Gently brake, steer, and accelerate. If the wheels start to slip, let up on the action you are taking, then go back to it.
3 places to look for ice: 1. Bridges and overpasses. 2. In shaded areas. 3. In tire tracks.
1. Power skid – Excessive acceleration. 2. Brake skid – Excessive braking 3. Spin out – Too fast around curves.
The basic cause of skidding is the loss of rolling grip between the tires and the road surface. When the wheels stop rolling, so does your ability to steer the car. Quit doing whatever caused you to skid. Power skid, take foot off gas. Brake skid, take foot off brake and pump them gently and slowly. Spin out, take foot off gas.
1. Rocking Technique 2. Put something under your tires to regain traction. 3. Weight in the back of your vehicle will help you from getting stuck.
Applying your brakes to slow, or stop quickly without locking your brakes. The key is applying the right amount of pressure. If you brake too hard you’ll skid. If you brake too light you won’t get stopped in time.
Always steer in the direction that the rear of your car is skidding. The way you want your car to go. Don’t give up when you are in a skid, you still might be able to correct it.
Adjust your speed depending on how hard the wind is blowing, and keep a firm grip on the steering wheel. When semi’s pass you. When driving out from under an overpass or tunnel.
Small light cars Motorcycles Vans Campers Cars pulling trailers Cars with a car top carrier
YYour temperature light indicates when your engine is too hot. Your engine is producing more heat than your cooling system can handle. IIf this happens, turn on your heater. This will draw the heat away from the engine.
IIf the temperature light stays on, pull over and turn the engine off. Once it cools, check your coolant level to make sure you have enough fluid. NNever open the radiator cap on a hot engine.
Be alert for exhaust leaks – carbon monoxide. Do not race a cold engine. Do not set your parking brake after driving through icy or slushy conditions.
Look and listen to traffic reports when the weather gets bad. Keep your windows, headlights, taillights, and license plates clear. Reduce speed according to conditions, and increase your following distance. Keep moving on snow and ice.
Watch for danger spots ahead. Use a lower gear on slippery roads. Avoid using cruise control. Have appropriate clothes in the car. (Gloves, hat, coat).