AP Physics--Motion

Summer Assignment 2
Graphing Relationships with Simple Motion
Due: July 27, 2012
I. Graphs and Motion Maps of Position, Velocity, and Acceleration.
a. General guidelines:
i. Forward/Right = (+)
ii. Reverse/Backwards/Left = (-)
iii. When “speeding up,” velocity and acceleration have the same sign.
iv. When “slowing down,” velocity and acceleration have opposite
signs.
v. Position is represented by “dots.”
vi. Velocity is represented by “solid arrows.”
vii. Acceleration is represented by “dashed arrows.”
b. Case 1 – Constant velocity, zero acceleration.
i. Constant velocity means that the velocity graph is horizontal.
ii. A constant velocity means the position graph has a constant slope.
iii. Examples:
x
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0
1

x
Summer Assignment 2
Graphing Relationships with Simple Motion
Due: July 27, 2012
v
a
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0
x
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0
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Summer Assignment 2
Graphing Relationships with Simple Motion
Due: July 27, 2012
c. Case 2 – Constant acceleration.
i. Constant acceleration means the velocity graph has a constant
slope.
ii. Constant acceleration also means that the position graph is
parabolic or hyperbolic.
iii. Remember: when velocity and acceleration have the same sign, the
object is “speeding up.”
iv. Examples:
x
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0
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x
Summer Assignment 2
Graphing Relationships with Simple Motion
Due: July 27, 2012
v
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0
x
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x
d. Other examples:
i. An object at rest, 10 m from the origin.
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Summer Assignment 2
Graphing Relationships with Simple Motion
Due: July 27, 2012
ii. An object starts at the origin and moves with a constant velocity of
7 m/s.
x
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t
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0
iii. An object starts at the origin at rest and accelerates at 4 m/s 2 .
x
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x
iv. Describe the following motion:
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0
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Summer Assignment 2
Graphing Relationships with Simple Motion
Due: July 27, 2012
v. Describe the following motion:
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0
vi. Describe the following motion:
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e. More complex examples:
i. Jason and Dan are next-door neighbors. Both leave their homes at
6:00 am. Dan jogs eastward. Jason starts at rest and then drives
eastward. Their combined position vs. time graph is shown below.
x
Jason
Dan
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a
50
t
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20
At time 0 s, who is ahead ___ Jason ___ Dan ___ Neither
At time 10 s, who is ahead ___ Jason ___ Dan ___ Neither
At time 20 s, who is ahead ___ Jason ___ Dan ___ Neither
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Summer Assignment 2
Graphing Relationships with Simple Motion
Due: July 27, 2012
At time 30 s, who is ahead ___ Jason ___ Dan ___ Neither
At time 0 s, who is moving faster ___ Jason ___ Dan ___ Neither
At time 10 s, who is moving faster ___ Jason ___ Dan ___ Neither
At time 20 s, who is moving faster ___ Jason ___ Dan ___ Neither
At time 30 s, who is moving faster ___ Jason ___ Dan ___ Neither
At time 0 s, who has more acceleration ___ Jason ___ Dan ___ Neither
At time 10s, who has more acceleration ___ Jason ___ Dan ___ Neither
At time 20s, who has more acceleration ___ Jason ___ Dan ___ Neither
At time 30s, who has more acceleration ___ Jason ___ Dan ___ Neither
ii. Jessica and Nicole’s graphs are show below.
x
v
a
50
Jessica
Nicole
t
t
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8 10 20
Jessica’s velocity is ___Positive ___Negative ___0.
Jessica’s acceleration is ___Positive ___Negative ___0.
Nicole’s velocity is ___Positive ___Negative ___0.
Nicole’s acceleration is ___Positive ___Negative ___0.
Note: 0 is greater than a negative number.
At time 0 s, who is ahead
At time 8 s, who is ahead
At time 10 s, who is ahead
At time 20 s, who is ahead
At time 30 s, who is ahead
At time 0 s, who is moving faster
At time 8 s, who is moving faster
At time 10 s, who is moving faster
At time 20 s, who is moving faster
At time 30 s, who is moving faster
At time 0 s, who has more acceleration
At time 8 s, who has more acceleration
At time 10 s, who has more acceleration
At time 20 s, who has more acceleration
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
___Jessica ___Nicole ___Neither
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Summer Assignment 2
Graphing Relationships with Simple Motion
Due: July 27, 2012
At time 30 s, who has more acceleration ___Jessica ___Nicole ___Neither
iii. Matthew and Nicolas’ graphs are below.
x
v
a
50
Matthew
Nicolas
t
t
t
10 20 42
At time 0 s, who is ahead
At time 10 s, who is ahead
At time 20 s, who is ahead
At time 30 s, who is ahead
At time 42 s, who is ahead
At time 50 s, who is ahead
At time 0 s, who is moving faster
At time 10 s, who is moving faster
At time 20 s, who is moving faster
At time 30 s, who is moving faster
At time 42 s, who is moving faster
At time 50 s, who is moving faster
At time 0 s, who has more acceleration
At time 10 s, who has more acceleration
At time 20 s, who has more acceleration
At time 30 s, who has more acceleration
At time 42 s, who has more acceleration
At time 50 s, who has more acceleration
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
___Matthew ___Nicolas ___Neither
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Summer Assignment 2
Graphing Relationships with Simple Motion
Due: July 27, 2012
iv.
One more…FOR NOW!
The ball starts at rest at the top of a hill. As the ball rolls down the hill,
the magnitude of the velocity:
____Increases ____Decreases ____Stays the same
As the ball rolls down the hill, the magnitude of its acceleration:
____Increases ____Decreases ____Stays the same
The ball starts at rest at the top of a hill. As the ball rolls down the hill,
the magnitude of the velocity:
____Increases ____Decreases ____Stays the same
As the ball rolls down the hill, the magnitude of its acceleration:
____Increases ____Decreases ____Stays the same
The ball starts at rest at the top of a hill. As the ball rolls down the hill,
the magnitude of the velocity:
____Increases ____Decreases ____Stays the same
As the ball rolls down the hill, the magnitude of its acceleration:
____Increases ____Decreases ____Stays the same
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