EVOC terminology Flashcards
Anti-Lock Brake System
Computer-controlled brake system designed to prevent wheel lock-up during heavy braking.
Apex (or Low Side)
The lowest portion of a vehicle’s path through a curve.
Balanced Hand Position
Maintaining a wide grip on a vehicle’s steering wheel.
Centrifugal Force (Center Fleeing)
The force that propels an object outward from the center of rotation.
Centripetal Force (Center Seeking)
The force that is necessary to keep an object moving in a circular path and is directed in ward toward the center of rotation.
Code 3
The operation of a patrol vehicle with red lights and siren activated, in compliance with California Vehicle Code Section 21055.
Coefficient of Friction
The measurement of cohesion between two surfaces.
Cohesion
The sticking power between two surfaces.
Countersteer
Turning the front wheels of a vehicle in the direction the rear of the vehicle is sliding.
Electronic Stability Control System
Computerized technology that improves a vehicle’s stability by detecting and reducing loss of traction.
Front End Swing
The action of the front end of the vehicle when backing: the front end swings to the right when backing to the left; the front end swings to the left when backing to the right.
High Side
The outside of a curve in a roadway.
Hydroplaning
Occurs when water on a road’s surface causes the tires of a vehicle to lose contact with it.
Impending Skid
A preliminary skid caused by maximum pressure on a
vehicle’s brake pedal short of locking the brakes.
Kinetic Energy
The energy possessed by a body in motion.
Momentum
The property of a moving body that determines the length of time required to bring it to rest when under the action of a constant force or movement.
Oversteer
The characteristic of a vehicle to tighten its turning radius as the rear end slips or skids toward the outside of a curve.
Potential Energy
The energy a body possesses by virtue of its position (e.g., a vehicle parked on a hill), or by virtue of displacement (e.g., the energy stored in a vehicle’s springs as they are stretched or compressed while the vehicle is traveling through a curve).
Power Slide (Four-Wheel Drift)
The controlled lateral skidding of a vehicle when the limits of cohesion are exceeded by all four tires.
Rear End Cheat
When turning left, a vehicle’s rear tires track to the left of the front tires. When a vehicle is turning right, the rear tires track to the right of the front tires.
Rolling Friction
The front wheels of a vehicle must be rolling, thereby creating rolling friction, in order to steer the vehicle.
Slip Angle
The turning radius of a vehicle becomes larger as the contact patch of each tire is distorted by increasing cornering force.
Space Cushion
The open area surrounding a vehicle in motion that provides an escape route to the front, rear, and sides.
Threshold Braking
Application of braking force to the point just prior to wheel lock-up. This braking technique is more efficient
at slowing a vehicle than locked-wheel braking.
Throttle
The vehicle’s accelerator pedal.
Time Spatial Judgment (Rate of Closure)
Judging the proper rate of deceleration necessary to successfully negotiate a curve or to avoid a hazard.
Tire Footprint
The contact area of a tire tread with the roadway.
Understeer
The tendency for a vehicle to continue in a straight line and resist turning from a direct course of travel.
Visual Horizon
The area and distance viewed by the driver of a vehicle when looking ahead.
Weight Transfer
Weight transfer to the rear axle of a vehicle caused by
forward acceleration.
Longitudinal Weight Transfer
Weight transfer to the front axle of a vehicle
caused by braking or deceleration.
Lateral Weight Transfer
Weight transfer of the front axle to the left when turning the vehicle to the right, and weight transfer of the front axle to the right when turning the vehicle to the left.
Brake fade
The loss of braking efficiency normally due to heat build-up resulting from excessive use of brakes.
