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Speed
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S=
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Speed decelerating to stop when factor and distance are known.
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S=
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Speed during decelerating to a stop across different surfaces with different factors.
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Sc=
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Combined Speed (To combine any number of speeds)
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S=
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To convert Velocity (FPS) to Speed (MPH)
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S=3.86
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Critical speed or curve or speed or vehicle leaving yawmarks when Radius, Drag factor and Super Elevation are known.
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Velocity
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V=a*t
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Velocity gained or lost when time and acceleration or deceleration factor is known.
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V=Vo +/- a*t
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Velocity at any time in an acceleration or deceleration when the initial velocity and acceleration or deceleration factor is known.
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V=
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Velocity at any distance when accelerating or decelerating when the acceleration or declaration factor is known
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V=S*1.466
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To convert speed (MPH) to velocity (FPS)
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Distance
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D=
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Distance to accelerate or decelerate to or from a stop, when speed and acceleration or declaration factor is known.
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D=16.1*f*(t2)
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Distance to accelerate or decelerate from a stop when acceleration or declaration factor and time is known
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D=V0*t+/-[.5*a*(t2)]
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Distance traveled during an acceleration or declaration from a known initial velocity when the acceleration or deceleration factor and time
is known.
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Time
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T=.25*
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Time to accelerate or decelerate from a stop when the acceleration or deceleration factor and distance is known.
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T=
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Time to accelerate or decelerate from a stop when velocity and acceleration or deceleration factor is known.
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T=
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Time to accelerate from one velocity to another when velocity final, velocity original and acceleration factor is known.
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T=
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Time to skid or slow from one velocity to another when velocity original, velocity final and declaration factor is known.
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Factors
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f=
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Drag factor if Force and Weight are known.
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f=
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Acceleration or deceleration factor when speed and distance are known.
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f=
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Acceleration or deceleration factor when velocity and time are known.
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f=
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Acceleration or deceleration factor when distance and time are known.
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f=
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Acceleration factor when unit accelerates, when velocity original, velocity final and time are known.
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f=
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Deceleration factor when unit decelerates, when velocity original, velocity final and time are known.
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Miscellaneous
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M=
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Percent (%) or grade or super elevation measured using a level.
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M=
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Mass is weight or object divided by gravity (32.2).
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Ke=1/2*M*V2
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Kinetic Energy
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R=
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Radius or curve or yaw marks when chord and middle ordinate is known.
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W1V1+W2V2= W1V3+W2V4
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Basic conversion or linear momentum equation.
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H=R-
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Tangent offset equation to calculate (H) offset from baseline at any measured distance, to plot ® Radius or curve.
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a=g*f
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Acceleration or deceleration rate when acceleration or deceleration factor is known.
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t=
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Time to travel a known distance at a constant velocity.
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D=V*t
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Distance traveled at a constant velocity and known time.
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V=
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Velocity to travel a known distance in a known time.
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Back to Accident Investigation
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