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Speed
Monroe
January 32, 2008
Speed ~ distance divided by time
Continents move in centimeters per year
Airplanes in kilometers per hour
American cars in miles per hour
Comets in miles per second
Bullets in feet per second
These are all measurements of speed
Average speed is over a longer period of time.
If Sam Swiftfoot can run 10 miles in 73 minutes, what is his average speed?
Average speed is over a longer period of time.
If Sam Swiftfoot can run 10 miles in 73 minutes, what is his average speed?
10 miles 60 minutes 8.22 miles
----------- x -------------- = ---------------
73 minutes 1 hour hour
Instantaneous Speed ~ is the speed during an instant of time. Look at your speedometer for a good idea.
There really is no such number as instantaneous speed, however, because one can always reduce time until it reaches zero, at which time the number becomes undefined. One cannot divide by zero.
Velocity ~ is the speed in GIVEN DIRECTION. This implies displacement instead of distance.
Velocity ~ is the speed in GIVEN DIRECTION. This implies displacement instead of distance.
Distance ~ is how far you move, along the face of the Earth, compared to a reference point.
Velocity ~ is the speed in GIVEN DIRECTION. This implies displacement instead of distance.
Distance ~ is how far you move, along the face of the Earth, compared to a reference point.
Displacement ~ is the distance between the starting point and the ending point of a movement.
A horse took 15 seconds to run around an oval track, that was 1/4 mile in length.
What is the total distance that he ran?
A horse took 15 seconds to run around an oval track, that was 1/4 mile in length.
What is his total displacement?
A horse took 15 seconds to run around an oval track, that was 1/4 mile in length.
What was his average speed?
A horse took 15 seconds to run around an oval track, that was 1/4 mile in length.
What was his average velocity?
What is the average speed of Chuck Norris, as he pursues the evil doers in the path shown below? Time is 25 minutes.
14 kilometers
24 kilometers
14 kilometers
Crime scene Arrest made in fast and heroic action
What is the average speed of Chuck Norris, as he pursues the evil doers in the path shown below? Time is 25 minutes.
14 kilometers
24 kilometers
14 kilometers
Crime scene Arrest made in fast and heroic action
52km÷25 min = 2.08km/min
What is the average velocity of Chuck Norris, as he pursues the evil doers in the path shown below? Time is 25 minutes.
14 kilometers
24 kilometers
14 kilometers
Crime scene Arrest made in fast and heroic action
What is the average velocity of Chuck Norris, as he pursues the evil doers in the path shown below? Time is 25 minutes.
14 kilometers
24 kilometers
14 kilometers
Crime scene Arrest made in fast and heroic action
24 km ÷ 25 min = .96km/min
What is the average speed of Chuck Norris, as he pursues the evil doers in the path shown below? Time is 25 minutes.
14 kilometers
24 kilometers
Crime scene
Arrest made in fast and heroic action
What is the average speed of Chuck Norris, as he pursues the evil doers in the path shown below? Time is 25 minutes.
14 kilometers
24 kilometers
Crime scene
Arrest made in fast and heroic action
38 km ÷ 25 = 1.52 km/min
What is the velocity of Chuck Norris, as he pursues the evil doers in the path shown below? Time is 25 minutes.
14 kilometers
24 kilometers
Crime scene
Arrest made in fast and heroic action
What is the velocity speed of Chuck Norris, as he pursues the evil doers in the path shown below? Time is 25 minutes.
14 kilometers
24 kilometers
Crime scene
Arrest made in fast and heroic action
142 + 242 =X2
1.11 km/min
How does displacement differ from distance?
How can speed be defined?
a. Change in speed divided by time
b. Change in velocity divided by time
c. How fast velocity is changing
d. How much force is placed on an object
What is the formula for speed?
a. Speed divided by time
b. Time divided by velocity
c. Distance divided by time
d. Distance divided by velocity
What does the slope on a distance/time graph indicate?
a. Displacement
b. Velocity
c. Time
d. Speed
Which person is moving most quickly?
Distance
Time
A
B
C
Which person is moving most quickly?
Distance
(km)
Time (min)
A
B
C
5
10
1 2 3 4 5
