Motion Notes Title = key idea Bullets = supporting detail or definition.
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Transcript of Motion Notes Title = key idea Bullets = supporting detail or definition.
Motion Notes
Title = key ideaBullets = supporting detail or definition
Speed
the rate which something moves
speed = distance time➗
s = d / t
units = meters / secondExample:If Billy jogs 10 meters in 5 seconds, what is his average speed?
10 meters 5 seconds = 10m/5s = 2 ➗m/s
Velocity
the rate which something moves in a specific direction
velocity = displacement time➗
v = d / t
units = meters / secondExample:If Bonnie jogs north 20 meters in 5 seconds, what is his average velocity?
20 meters 5 seconds = 20m/5s = 4 m/s north➗
Velocity
Velocity
vector quantity = direction matters
displacement = change in position
Example:Sanchez smacks a home run into the outfield. He runs around all bases, a total of about 110 m. It takes him 20 seconds to reach home plate.
a. Calculate Sanchez’s average speedb. Calculate Sanchez’s average velocity
Example:Sanchez smacks a home run into the outfield. He runs around all bases, a total of about 110 m. It takes him 20 seconds to reach home plate.
a. Calculate Sanchez’s average speed
Speed = distance / time
Speed = 110 meters / 20 seconds
Speed = 5.5 m/s
Example:Sanchez smacks a home run into the outfield. He runs around all bases, a total of about 110 m. It takes him 20 seconds to reach home plate.
b. Calculate Sanchez’s average velocity
Velocity = displacement / time
Velocity = 0 meters / 20 seconds
Velocity = 0 m/s
Acceleration
the rate at which velocity changes
increase in velocity = positive acceleration
decrease in velocity = negative acceleration
acceleration = change in velocity / time
a = (v2- v1) / t
units = m/s/s or m/s2
Acceleration
a vector quantity, so acceleration changes with...
direction
speed
Example:My dog Bailey is sitting on the patio watching a squirrel. She suddenly starts running at 2 m/s towards the tree. She runs in a straight path towards the tree for 5 seconds. What is her average acceleration?
Acceleration = (v2- v1) / t ● V2 = 2 m/s towards the tree● V1 = 0 m/s facing towards the tree● t = 5 seconds
a = (2 m/s - 0 m/s) / 5 sa = (2 m/s) / 5 sa = 0.4 m/s/s
Is this positive or negative acceleration?
Example:Aubrey is driving to school at 20 m/s. As she enters the school zone she slows to 9 m/s. It takes her 5 seconds to fully slow down. What is her average acceleration during those 5 seconds on this straight road?
Acceleration = (v2- v1) / t ● V2 = 9 m/s straight● V1 = 20 m/s straight● t = 5 seconds
a = (9 m/s - 20 m/s) / 5 sa = (-11 m/s) / 5 sa = -2.2 m/s/s
Is this positive or negative acceleration?
Acceleration
1. If acceleration equals zero, can there be movement occurring? Explain your thinking…
Yes. For example, velocity can be constant at 10 m/s and acceleration won’t change.
Motion Analysis Practice
http://www.physicsclassroom.com/Physics-Interactives/1-D-Kinematics/Name-That-Motion/Name-That-Motion-Interactive