Audio Transcript Auto-generated
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all right and listen to we're gonna be covering speed
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control. So to drive safely, you must be able to
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maneuver your vehicle properly.
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You can do so by knowing your vehicles limits.
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When changing lanes or passing, for example, you need to
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have an idea of how much time and distance your
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vehicle requires to move ahead of other vehicles.
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Learning to judge the time and space each maneuver takes
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will minimize your risk as well.
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Adjusting your speed based on visibility, traffic and road conditions.
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There are several ways to adjust the speed of your
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vehicle. You can go faster, maintain a constant speed or
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slow down by changing the pressure you put on the
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accelerator or brake pedal.
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Depending on the amount of pressure on the brake pedal,
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you can brake lightly, break harder, lock the brakes or
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engage the anti lock braking system function.
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So we're essentially just going to talk about stopping and
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moving, Uh, and how to do that safely here, guys.
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So some words we're going to be definitely using here
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are acceleration, deceleration and speed.
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Um, and it's the number one cause of all crashes
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in the state of Virginia and nationwide So it's why
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we are starting with this before we get to other
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topics about crashes.
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So for safety, how acceleration, deceleration and speed related.
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So we're gonna start with acceleration or your vehicle picking
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up speed.
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Increasing speed.
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When drivers say the vehicle has good acceleration, they mean
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their vehicle is able to increase speed relatively quickly.
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Several factors affect of vehicles acceleration, including the power of
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the engine, the transmission and do differential gear ratios.
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Adhesion between the drive wheels and the road surface and
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the weight of the engine is pulling.
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That's a lot of words, but all those things are
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having to do with acceleration, so the amount of time
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it takes to accelerate is known as the rate of
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acceleration. So what is acceleration and how are acceleration and
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speed related?
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Uh, so acceleration is going to be going Speed is
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how fast that is going.
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So, uh, just give it a little brief idea of
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how those two things are related.
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So if we start going fast, we better know how
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to decelerate or decrease their speed.
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On the other hand is up word.
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That means decreasing speed or slowing down the time it
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takes to decelerate from one speed to another is known
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as the rate of deceleration, so the time it takes
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to slow down from one point to another, so speed
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and acceleration are closely linked.
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Since the rate of acceleration varies with speed at higher
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speeds, for example, a vehicle's rate of acceleration will be
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lower. It generally takes more time to accelerate from 45
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MPH to 55 MPH than it does for 20 to
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30. Understanding this principle is important for risk management.
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For example, you must allow more time to pass another
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vehicle when you're traveling at 50 MPH than when you're
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moving at 30 MPH, because it will take longer to
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accelerate. Equally important to keep in mind is that deceleration
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rates like acceleration rates, vary with speed at higher speeds.
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Your vehicles rate of deceleration is lower, so a vehicle
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traveling at 60 MPH needs a lot more time and
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space to slow and brake to a stop within the
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same vehicle, traveling at 30 MPH.
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It's a question, too.
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What is Deceleration and Howard Deceleration and speed related, and
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just to give you a little bit more.
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If you're going 50 MPH down the road and it's
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dry payment, it's gonna take you roughly about 200 ft
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to come to a stop at 50 MPH.
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We get going 60 and it takes us almost three
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almost an extra 100 ft.
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So the faster we're going, the more space we have
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to allow ourselves to come to that complete stop.
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So the weight of the vehicle also affects its rate
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of acceleration and deceleration.
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Many of us, especially here in Madison, we like big
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trucks and I drive a truck.
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Um, so if you take a truck next to a
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sports car, the radial acceleration is gonna be much different
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due to the weight of the vehicle.
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So heavy truck, for example, needs much more time and
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distance to accelerate.
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It also needs more time to decelerate.
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In contrast, a motorcycle which weighs much less than the
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vehicle takes less time and less distance to accelerate or
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decelerate. Alright, before we get to breaking, which is what
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we're gonna be going over next, we need to know
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it's easy to maintain your speed on a flat, straight
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road. But the ability of a vehicle to maintain a
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given speed when challenged by terrain varies greatly.
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Large. Large passenger vehicles with high high horsepower, six or
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eight cylinder engines and mid size and sports sedans with
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turbocharged small engines generally have good acceleration and can maintain
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their speed.
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Climbing up a hill and underpowered subcompact vehicle, however, may
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not be able to hold its feed because of its
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small four cylinder engine.
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Very large vehicles also have difficulty maintaining their speed.
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Tractor trailer rigs and interstate buses have huge engines, but
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these large vehicles accelerate very slowly because they weigh a
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lot. One important thing to note is monitoring your speed,
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and when we first get started, we pay so much
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attention to our speedometer while we're driving.
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And then all of a sudden we get driving and
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we're flowing with traffic and you look down and you're
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going 15 miles an hour above the speed limit.
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But you're flowing with traffic, so what do you need
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to do?
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All right, safety wise, you should go as close to
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the speed limit as possible.
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Let people go around you, but you need to be
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thinking about yourself and your own safety, uh, to begin
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with. So if we are monitoring our speed, we notice
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that we're going faster than what we need to be
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or faster than what the road allows do whether due
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to time of day or whatever else we need, we
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better know how to break.
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So we're gonna go over a couple of different braking
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techniques here.
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Smooth braking, braking to a stop emergency braking and threshold
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braking. So speed control by breaking.
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Putting on brakes reduces your speed and allows you to
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stop. As a driver, you have to slow down and
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stop your vehicle many times under both planned and unexpected
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circumstances. Red lights stop signs, right or left turns pedestrians
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running across the street, Vehicles cutting in front of you.
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These and countless other situations will require you to apply
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your brakes now of these.
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Hopefully, we're going to be practicing smooth braking more than
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anything else and almost think about when I'm breaking or
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when I'm accelerating is the pedal has a balloon underneath
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of it, and I want to press.
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So I never popped that balloon.
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All right, now it's something runs out in front of
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us. Obviously, we've got to put some pressure down there.
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But majority of the time we want to act like
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we're stepping on a balloon with enough pressure that we
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will not pop that balloon.
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So that's how smooth braking comes in.
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As you drive a particular vehicle, you will get a
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fuel for applying on the right amount of pressure on
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the brake pedal when you need to stop.
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Your goal is to stop just at the right spot,
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neither over shooting nor under shooting your desired stopping point.
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This makes for a safer, smoother ride for you and
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your passengers.
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The amount of foot pressure requires to break or a
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stop depends mainly on your speed.
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If you're going fast, you will have to break longer
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to stop.
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Other factors include include the size and weight of the
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vehicle, the type of breaks your vehicle you're maneuvering space
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and the road surface.
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As you practice driving and become more experience, you'll get
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better at judging the distance needed to bring your vehicle
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to a smooth stop.
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For effective control of brake pressure, position to hell of
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your foot between and in front of the accelerator and
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the brake pedal.
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This way you'll be able to apply pressure to the
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brakes with your toes, which are more sensitive than the
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ball of your foot, so you can easily increase or
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decrease pressure in small amounts as needed.
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So smooth braking you want to be.
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It's all about pressure.
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Okay, so if we're breaking to a stop, check your
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mirrors for any vehicles that may be following you.
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If a vehicle is following you, lightly tap the brake
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pedal you're flashing.
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Brake lights will warn other drivers when you intend to
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stop. Apply smooth, steady, firm pressure to the brake pedal,
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easing up slightly as you come to a halt.
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If your vehicle has a manual transmission, you will need
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to press down the clutch as you stop.
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If your car has an automatic transmission, leave the transmission
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and drive if you plan to move ahead within a
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minute or so, as when you stopped for a red
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light. So now let's get into emergency braking.
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So if a driver or pedestrian suddenly enters your path
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of travel, you'll need to stop the vehicle as quickly
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as possible.
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However, you don't want to slam on the brakes so
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hard the wheels lock or stop turning, which is possible
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to do with vehicles that are not equipped with antilock
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brakes. So we're gonna talk about a B s or
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anti lock brakes.
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Most of the vehicles that you all will start driving
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probably are going to be, um, are going to have
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a B s brakes.
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But if you drive something much older, it's good to
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practice on how to do this, because if it doesn't
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have a BS, you lose the ability to steer the
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vehicle. A B s is going to allow you to
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do that.
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So threshold braking and a B s breaking Go practice
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this. You know, the the parking lot back here at
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the back of the high school is great to practice
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a B s because it's weird when you first feel
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it. So threshold braking is pressing, pressing down the brakes
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to appoint just short of the wheels locking up.
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So this is really putting good pressure on there, but
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you can still drive everything you need to, and then
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new systems have a B s.
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So if you have to press down hard most vehicles
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now, what you're gonna feel is this pulsing sensation of
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the pedal and what that is.
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It's releasing air to allow you to still use the
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steering wheel.
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So somebody is running out in front of you.
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Dear is jumping out in front of you.
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You press down the brake hard, but you can still
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steer in one direction.
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Without that, what you would do is go into a
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skid and not be allowed to steer the vehicle.
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So a BS is a good thing.
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UH, it can protect you in case of an emergency,
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So antilock brakes shouldn't make much difference in stopping distance
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on Dr Rhodes.
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But they do help drivers maintain control of the vehicle
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during sudden emergency stops, even on wet or slippery roads.
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Antilock brakes work with the cars.
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Normal service breaks.
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They have speed sensors mounted at each wheel and the
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secondary electro hydraulic braking.
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Since, uh, circuit anti lock brakes prevent tires from skidding
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by monitoring the speed of each wheel, automatically pulsing the
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brake pressure up to 20 times per second on any
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wheels where skidding is detected with antilock brakes, you will
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feel a pulsing against your foot on the brake pedal
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when applying constant pressure to the brake.
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This is normal and indicates that the A B s
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is working.
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So a B s.
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It's gonna be awkward at first, but just get used
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to it.
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Is there for safety?
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So what are some of the different ways of breaking
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in a vehicle?
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So we just named a couple there, and then what
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is a B s?
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And how does the system work?
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I can tell you there's some really good videos on
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YouTube on what is a B s.
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Typically watch one of these in class, but I definitely
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suggest going out and watching on and learning how to
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drive with a B s brakes.
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It is a little bit different, Uh, and at first,
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when you feel that you might want to just, like,
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let go of the brakes.
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But obviously we're trying to stop, so you want to
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apply that pressure.
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Alright, so that's less than two.
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You'll have some review or you have the review questions.
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Go ahead and submit those and we'll move on the
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less than three