This document defines and explains key concepts related to speed and velocity in physics. It discusses average speed as the rate of change of distance over time, with common units like meters/second. Velocity differs from speed in that it includes an object's direction of motion. Uniform motion refers to constant speed and direction over time. Instantaneous speed indicates an object's speed at a single moment. Graphs can depict changes in speed and velocity over time.

1. Physics: SpeedPhysics: Speed
and Velocityand Velocity

2. Average SpeedAverage Speed
Rate at which an objectRate at which an object
movesmoves
Units are in distance / timeUnits are in distance / time
Ex. Meters/second,Ex. Meters/second,
centimeters/hourcentimeters/hour

3. Units of DistanceUnits of Distance
Miles (mi)Miles (mi)
Centimeters (cm)Centimeters (cm)
Feet (ft)Feet (ft)
Light year (Ly)Light year (Ly)
Meters (m)Meters (m)

4. Units of TimeUnits of Time
Seconds (s)Seconds (s)
Hours (hr)Hours (hr)
Minutes (min)Minutes (min)
Years (yr)Years (yr)

5. Equation forEquation for
Average SpeedAverage Speed
Speed =Speed = ∆∆d/d/∆∆t =t =
change inchange in
distance/change indistance/change in
timetime

6. VELOCITYVELOCITY
Velocity is speed with aVelocity is speed with a
directiondirection
Ex. A car is travelingEx. A car is traveling
12 mph west12 mph west
V =V = ∆∆d /d / ∆∆t = change int = change in
position/ change in timeposition/ change in time

7. Uniform MotionUniform Motion
Motion at a constant speedMotion at a constant speed
and directionand direction
Also called “constantAlso called “constant
velocity”velocity”

8. InstantaneousInstantaneous
SpeedSpeed
 Speed of an object at a particularSpeed of an object at a particular
moment or “instant” of timemoment or “instant” of time
 Ex. Reading on a speedometerEx. Reading on a speedometer

9. Graphs of Speed/Graphs of Speed/
VelocityVelocity
 Constant velocityConstant velocity
 Slope gives you velocitySlope gives you velocity

10. Speed GraphsSpeed Graphs
cont’dcont’d
Increasing SpeedIncreasing Speed

11. d(m)
t(s)
A
Object is not moving, speed is
0