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Warm Up 1)
2)
3)
Acceleration
checkout www. physicsclassroom.com
Distance - a scalar quantity. - "how much ground an object has covered" during its motion. - additive total of all the displacements
Displacement - a vector quantity. -"how far out of place an object is" - the object's overall change in position.
6 m
6 m
3 m3 m
Speed -is a scalar quantity. - refers to "how fast an object is moving." -speed is the rate at which an object covers distance.
Velocity -is a vector quantity. - refers to "the rate at which an object changes its position."
Average Speed Distance TraveledTime of Travel
=
Average Velocity Δ positiontime
= = displacementtime
http://phet.colorado.edu/en/simulation/moving-man
Acceleration - is a vector quantity-that is defined as the rate at which an object changes its velocity-an object is accelerating if it is changing its velocity.
Note: acceleration is not moving fast, andif the velocity isn't changing then the acceleration equals zero.
-Velocity is increasing or decreasing (Deceleration)
- same speed different direction?
Circular motion
or
Time IntervalAve. Velocity During Time Interval
Distance Traveled During Time Interval
Total Distance Traveled from 0s to End of Time Interval
0 - 1 s ~ 5 m/s ~ 5 m ~ 5 m
1 -2 s ~ 15 m/s ~ 15 m ~ 20 m
2 - 3 s ~ 25 m/s ~ 25 m ~ 45 m
3 - 4 s ~ 35 m/s ~ 35 m ~ 80 m
Determine the Average acceleration based on the following data.
Average Acceleration Δ velocitytime
= = vf - vi
time
Units: (m/s)/s (km/hr)/s(mi/hr)/s
Determining Average Acceleration From a (v vs t) Graph
Direction of Acceleration
Depends on:
-is the object slowing down or speeding up,-is the object going left or right (+ve or -ve)
Rule of Thumb
If the object is slowing down then the acceleration is opposite to the direction of the velocity.
Compare the Velocities and Accelerations from the Graphs (v vs t)
Page 41
Is this train accelerating?
Special Case: Acceleration as a result of changing directions.
An object can move with constant speed and still be accelerating.
An object moving on a curve (and therefore changing direction) is accelerating.
Pages 33-41 in blue workbook
Pages 7 - 10 in yellow workbook