Chapter 5
Natural Laws
and
Car Control
What is gravity?

Gravity
the force that pulls things towards the earth
How does gravity affect you when
driving?

uphill/downhill driving- shift to a lower gear
What is the “center of gravity”?

High Center of Gravity
the point at which an objects weight is evenly
distributed
How does center of gravity affect your car
and its driving ability?
Low Center of Gravity
How will driving uphill and downhill affect
your stopping distance?
Which vehicle to the right has the fastest
stopping ability? why?
Energy of Motion and Stopping Distance
SPEED
What 2 things make up
energy of motion? (how an
object moves)

Depends on speed and weight
How does speed affect
stopping distance?



SQUARE the change in speedfor example:
double the speed = 4 times
distance to stop (60 ft)
triple the speed = 9 times
distance to stop (135 ft)
How does weight affect
stopping distance?

Double the weight= 2 times
distance to stop
WEIGHT
Total Stopping
Distance
Perception Distance= the
distance you travel while
identifying a situation
+
Reaction Distance= the
distance you travel from the
time you identify a hazard
and decide to brake
+
Braking Distance= the
distance you travel from the
time you first apply the
brakes to a full stop
Braking Distance
List 7 factors that
affect braking
distance






speed
vehicle condition
road surface
driver ability
ABS
Hills
Load
Traction and Friction
What controls your car?




steering wheel
brake pedal
accelerator
4 tires- most important
What is friction?
The gripping action that keeps the tire from
slipping
What is tread?



Allows water to flow away from the tire
How can you check for TREAD WEAR on your
tires?
What affects your cars traction?
tread
inflation of tires
Tire Inflation
More of the tire is touching
the surface
Outer edges of the tire are
touching the surface- where
would you find the most
wear and tear?
Center of tire is touching the
surface- where would you
find the most wear and tear?
Roller Coasters
Banked Curve
Where else would you
find a BANKED CURVE?
Race Track
What is a BANKED
CURVE?

A road built higher on
the outside than on the
inside to keep cars on
the road!
Motorcycle vs Car
Force of Impact =
speed + weight + dist traveled
Controlling the Force of Impact
How hard one moving object hits another object = force of impact
Speed + Weight+ Distance traveled = force of impact
The most important factor in determining how hard an
object hits is?

SPEED- slow down!
What safety features on
cars can help control
the force of impact?
Show Crash Physics Video
SEAT BELT USAGE
3 collisions occur in a
crash- what are they?
Turn to the person next
to you and discuss if
YOU THINK THERE
SHOULD BE A
SEATBELT LAW
REQUIRING YOU TO
WEAR A SEATBELT?
WHY OR WHY NOT?
Show seatbelt video
Active Restraints


safety belts
car seats
Until what age do
children have to be in
some sort of car seat?
Passive Restraints

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head restraints
air bags
bumpers
side door beams
reinforced windshield
steering column
padded dash
Side Impact Collision
Safety features?
Crazy Cats