Motion
Observing
To observe an object in motion, you must use
a referenced object. The one sitting still is considered
to be the reference point.
When an object changes position over time, compared
to the reference point, the object is said to be in motion
When an object is at rest, what
is its speed?
2 mph
1 mph
3 mph
0 mph
87%
ph
0m
3m
ph
1m
ph
7%
ph
7%
0%
2m
1.
2.
3.
4.
Motion is change in ____.
56%
28%
11%
on
po
sit
i
er
ey
el
in
cit
y
6%
ve
lo
speed
velocity
eyeliner
position
sp
ee
d
1.
2.
3.
4.
A reference point for determining
position and motion could be
Cloud
Building
A moving object
All of the above
61%
28%
11%
ab
o.
..
he
of
t
ov
in
m
A
Al
l
go
bj
ec
...
in
g
Bu
ild
ud
0%
Cl
o
1.
2.
3.
4.
Chemistry
Inertia
Inertia is a function of mass.
Inertia - tendency of an object to resist changes
in its direction
In other words an object stays at rest until
something causes it to move
Massive objects have large inertia
Small objects have small inertia
A person in a head-on car collision who is not
wearing a seat belt continues to move forward at
the original speed of the car because of ____.
44%
39%
17%
er
kd
r iv
Dr
un
Gr
av
i
e
fo
rc
ed
nc
ty
0%
Ba
la
Inertia
Balanced force
Gravity
Drunk driver
In
er
t ia
1.
2.
3.
4.
Which one of the following
objects has the greatest inertia?
pencil
Bowling ball
Baseball
Your head
78%
ea
d
6%
Yo
ur
h
Ba
se
ba
l
Bo
w
lin
gb
al
l
il
l
11%
6%
pe
nc
1.
2.
3.
4.
Motion
Speed
the rate at which an object moves
two variables need to be considered
a. distance
b. time
therefore:
speed = distance
time (s)
The distance traveled divided by the time it
took to travel that distance determines an
object's
Acceleration
Position
Speed
Force
59%
35%
6%
Fo
rc
e
Sp
ee
d
on
Po
sit
i
el
er
at
io
n
0%
Ac
c
1.
2.
3.
4.
The SI unit for speed is
Km/foot
feet/second
meter/second
mile/hour
62%
23%
15%
ur
ile
/h
o
m
se
co
et
er
/
m
fe
et
/s
ec
on
nd
d
t
0%
Km
/f
oo
1.
2.
3.
4.
Motion
Average speed is a measure of the distance traveled in a given period of time;
it is sometimes referred to as the distance per time ratio. Suppose that during
your trip to school, you traveled a distance of 5 miles and the trip lasted
0.2 hours (12 minutes). The average speed of your car could be determined
as
Motion
Velocity
the speed of an object in a particular direction
For example: 15 m/s east
or 22 m/s southwest
velocity always includes which way; N, S, E or W
Velocity is determined by speed
and direction
75%
Fa
l
se
25%
Tr
ue
1. True
2. False
Motion
Resultant velocity
this calculation is determined as follows
How fast is the boy moving?
a. if velocity is in the same direction
e.g.
b. if velocity is in opposite directions
e.g.
If a bus is traveling south at 15 mph and a
boy stands and walks north at 1 mph what is
the resultant velocity
1. 15 mph
100%
2. 1 mph
3. 14 mph
4. 16 mph
16
14
m
ph
0%
m
ph
0%
1m
ph
15
m
ph
0%
If a bus is traveling south at 15 mph and a
boy stands and walks south at 1 mph what
is the resultant velocity
1. 15 mph
56%
2. 1 mph
3. 14 mph
33%
4. 16 mph
m
ph
16
14
m
ph
6%
1m
ph
15
m
ph
6%
Motion
Acceleration
is the rate at which velocity changes
to apply a force to an object to make it either slow-down,
speed-up or change direction.
To calculate acceleration:
Acceleration = final velocity– starting velocity
time it takes to change velocity (s)
= mps
s
Motion
What is the acceleration of a dragster that goes from 0 to
300 mps in 5 seconds?
100 mph/s
600 mph/s
60 mps/s
50 mph/s
56%
28%
11%
s
50
m
ph
/
ps
/s
60
m
s
ph
/
m
60
0
m
ph
/
s
6%
10
0
1.
2.
3.
4.
The acceleration of an object
1. Does not deal with force
2. is always opposite of the force
that was applied.
3. is always in the same direction
as the force.
4. None of the above
44%
28%
22%
e.
..
...
4.
No
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of
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sa
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3.
i
ay
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2.
i
1.
Do
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. ..
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6%
Acceleration of an object
1. Slows down with
increase in weight
2. Increases with
force
3. Is in the same
direction
4. All of the above
53%
24%
18%
ab
o.
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of
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Is
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it h
.. .
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Slo
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..
6%
Observe the animation of the three cars below. Which car or cars
(red, green, and/or blue) are undergoing an acceleration?
Study each car individually in order to determine the answer.
Now that you've answered the first question correctly, try this one:
which car (red, green, or blue) experiences the greatest acceleration?
As a final test of your understanding, consider the position-time graph at
the right. Each one of the three lines on the position-time graph corresponds
to the motion of one of the three cars. Match the appropriate line to the
particular color of car.
Motion
Force
either a push or a pull
Unbalanced force
produces a change in acceleration
net force is greater than zero
Balanced force
produces no acceleration
net force is zero
Motion
Net force is the combination of 2 forces
A force is which one of these?
Push
Pull
Push or Pull
None of the above
94%
th
of
No
ne
Pu
sh
or
ea
Pu
ll
b.
..
0%
l
0%
Pu
l
6%
Pu
sh
1.
2.
3.
4.
When two birds are pulling on a worm and
the worm moves toward the first bird, you
know that the forces are ____.
Balanced
Unbalanced
Action-reaction
Unfair
94%
r
.. .
Ac
t
io
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re
ac
tio
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ce
d
Un
ba
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nc
0%
Un
fa
i
6%
0%
Ba
la
1.
2.
3.
4.
Which of the following is NOT an
example of a force being exerted?
1. Pushing open a
door
2. Sitting in a chair
3. Texting
4. None of the above
65%
18% 18%
No
ne
of
th
ea
b.
..
Te
xt
in
g
c. .
.
a
n
gi
Sit
tin
Pu
sh
i
ng
o
pe
n
a.
..
0%
Balanced forces applied to an
object makes that object
Stay at rest
Change direction
Accelerate
Slows down
65%
24%
Ch
a
n
sd
ow
w
Slo
el
er
at
e
6%
Ac
c
ng
e
di
ya
tr
re
ct
io
n
es
t
6%
St
a
1.
2.
3.
4.
You have made a house of cards on top of your table.
Suddenly, a gust of wind blows through an open window
and your house of cards comes tumbling down. The wind
applied ____ to your house of cards.
Gravity
Balanced
Friction
Centipedal
Unbalanced
39%
28%
22%
11%
an
ce
d
Un
ba
l
ed
al
Ce
nt
ip
Fr
ict
io
n
Ba
la
nc
ty
ed
0%
Gr
av
i
1.
2.
3.
4.
5.
Motion
Friction
force that opposes motion between two
surfaces that are touching
hills and valleys
Greater the force, greater the friction
The force that opposes motion
Gravitational
Balanced
Unbalanced
Friction
57%
36%
7%
Fr
ict
io
n
an
ce
d
Un
ba
l
nc
Ba
la
ta
t
io
na
l
ed
0%
Gr
av
i
1.
2.
3.
4.
One way to increase friction is
to use
wax
water
sand
oil
57%
21%
14%
oi
l
sa
nd
at
er
w
ax
7%
w
1.
2.
3.
4.
Gravity and Motion
Motion
all objects fall to the ground at the same rate
What would hit first, elephant or feather?
how? difference in force is canceled by the difference in mass
Motion
Air resistance slows down acceleration
air resistance continues to increase until it matches
the downward force of gravity
object then falls at a constant velocity
called terminal velocity
Motion
Another example of terminal velocity
Remember, the increase in air resistance continues
till it is even with gravity
Motion
Free fall
no air resistance
can only occur in a vacuum
the only force acting is gravity
Motion
Newton’s Laws of Motion
Three laws that relate force to the motion of objects
First law aka. law of inertia
An object at rest tends to stay at rest and an
object in motion tends to stay in motion with the
same speed and in the same direction unless acted
upon by an unbalanced force.
Examples of Newton’s 1st Law
Newton’s first law of motion
applies
Moving objects
No moving objects
Speed
Both 1 and 3
0%
Bo
th
1
an
d
3
Sp
ee
d
0%
10
No
m
ov
in
go
ob
je
ct
s
ng
0%
bj
e.
..
0%
M
ov
i
1.
2.
3.
4.
Countdown
According to Newton’s first law of motion, a
moving object that is not acted on by an
unbalanced force will
Remain in motion
Stop
Blow up
Accelerate
e
0%
el
er
at
ow
up
0%
Bl
St
op
0%
Ac
c
n
in
m
ot
i..
.
0%
Re
m
ai
1.
2.
3.
4.
10
Countdown
Newton’s first law of motion states that an
object stays at rest unless a(n) ____ acts on
it.
Balanced force
Gravitational force
Unbalanced force
Friction force
e
fo
rc
fo
r
an
ce
d
0%
Fr
ict
io
n
..
Un
ba
l
Gr
av
i
ta
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io
na
l.
fo
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nc
0%
...
0%
e
0%
Ba
la
1.
2.
3.
4.
10
Countdown
Motion
Second Law due to unbalanced force
that the acceleration of an object is dependent
upon two variables
a. the net force acting upon the object and
b. the mass of the object
Examples of Newton’s 2nd Law
Motion
Third Law
that for every action (force) in nature,
there is an equal and opposite reaction; force pairs
in other words: if object A exerts a force on object B,
then object B also exerts an equal force on object A
note: we are only talking about forces
Examples of Newton’s 3rd Law
Motion
Momentum
property of a moving object that depends
on the object’s mass and velocity
in other words: more momentum an object has the
harder it is to stop the object
Conservation (constant) of momentum
That is, the momentum lost by object 1
is equal to the momentum gained by object 2
Motion
Energy
the ability to do work
remember, work is a transfer of energy so therefore
work only occurs if the force and motion are in the
same direction
Work = F x d; force times distance
since force is in Newtons (N) and distance
is in meters the new label is J or Joules
Motion
Energy of Motion
called kinetic energy
as long as an object is moving there is kinetic energy
kinetic energy depends on mass and velocity
creating work
Motion
Energy of position
called potential energy
gravitational potential energy depends
on weight and height
tells us about stored energy that has the
capacity to do work
Motion
Mechanical energy
kinetic energy + potential energy
as the height decreases the PE also decreases
as the speed increases so does the kinetic energy
Types of energy
Motion
Motion
Conservation of energy
energy can be neither created nor destroyed
total amount of energy in a closed system is always the
same
with conversion of energy you always get thermal energy
what are the energies in the rollercoaster ride?
Motion
Temperature
temperature depends on the kinetic energy
of the particles
as a substance gets hotter, it’s particles moves faster
Motion
Temperature conversion
Motion
Heat
transfer of energy between objects of
different temperatures
energy is transferred from higher temperatures to
lower temperatures
Motion
Types of energy transfer
a. conduction – heat transfer by direct contact
higher kinetic energy to lower
kinetic energy
b. convection – heat transfer by movement
of liquid or gas
c. radiation – heat transfer as
electromagnetic waves