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Check Point #1 Review
4A: Motion Graphs
4 purposes!
 Display some type of motion: distance,
displacement (position), velocity
(speed), and acceleration vs. time. See
Graph attachment!
1. Distance vs time: distance covered in a
certain amount of time.
Slope= SPEED!
2. Displacement vs. time: distance from
start point in a certain amount of time.
Slope=Velocity!
3. Velocity vs. time: object’s velocity in a
certain amount of time
Slope=Acceleration!
4. Acceleration vs. time: object’s
acceleration in a certain amount of time
Make sure you pay attention to the axes!
 You can also find the displacement from
a velocity vs time graph by finding the
area under the plotted line.
3. If vectors go in opposite directions:
SUBTRACT!
If they make a right angle like:
Use Pythagorean Theorem to solve for
third side. This is on the front page of
the formula sheet under Force and
Motion! THIS IS THE DISPLACEMENT!
 Velocity: change in displacement over
time
 Acceleration: change in velocity over
time
Advanced Kinematics: combine the above to
find derived variables.
Remember if an object STARTS from rest,
Initial velocity=0
If an object ends at rest, final velocity= 0.
ALL EQUATIONS THAT YOU NEED FOR
THIS TEK ARE ON THE FRONT PAGE OF
THE FORMULAR SHEET IN THE FORCE
AND MOTION SECTION!
Break the area into shapes and calculate the
area of each shape.
Area of triangle = ½ bh
Area of rectangle= LW
4B: Kinematics
 Distance: how far an object travels
 Displacement: how far an object travels
from its start position
1. Remember, Draw out whatever they are
telling you!
2. If vectors go in the same direction: ADD!
Use the GUESS Method
 Given
 Unknown
 Equation- Use the variables in the Given
and Unknown to determine which
equation to use!
 Substitute
 Solve
4C: Projectile & Circular Motion
 Projectile Motion- an object in which
gravity is the only force that acts on it!
 For a horizontally launched object,
initial vertical velocity is zero!
Ex. Canon ball, bullet shot from gun
Check Point #1 Review
 For a object launched at angle!, at its
highest point, there is no vertical
velocity!
 Ex. Field goal in football
V=0 m/s
 Newton’s 2nd Law proves that different
masses accelerate to the earth at the
same rate, but with different forces.
 Bigger masses generate BIGGER
FORCES!
Newton’s Third Law
 For every action there is an equal and
opposite reaction.
 I am sitting on chair. I exert a force on
the chair and the chair exerts a force on
me!
4E: Free Body Diagrams
Circular Motion
 Centripetal means “toward the center,”
or “center-seeking.” Will ALWAYS point
towards the center!
 Centripetal acceleration: the rate of
change in the tangential velocity
 Velocity is always perpendicular to the
centripetal force.
Free body diagrams- Used to show the relative
magnitude and direction of all forces acting on
an object using vectors
4 common forces
 Gravity: points downward, attraction of
an object to earth
 Normal force: counteracts gravity, points
upward
Important: Gravity=Normal force. ALWAYS!
Fn
4D: Newton’s Laws of Motion
Newton’s First Law
 An object in motion will stay in motion or
at rest unless acted upon by an outside
UNBALANCED force.
 Inertia- tendency of an object to travel in
a straight line.
Newton’s Second Law
 Force equals mass times acceleration.
 F=ma
 Sometimes, you will not be given
𝑣𝑓−𝑣𝑖
acceleration. So F=m 𝑡
 On front page of formula sheet under
Force and Motion
Right!
Fg
Fn
Wrong!
Fg
Meaning these vectors would be the same size
in opposite directions
 Applied force: shows the force applied
to an object. May point in any direction
but normally left and right
 Friction: OPPOSES Motion. Points in
the opposite direction as applied force.
ALWAYS!
 IMPORTANT: If Friction > Applied force,
object will not move!
4F: Frame of Reference

 Force given in Newtons
 All motion is relative!
 All motion is measured with respect to a
particular frame of reference.
 Pay attention to who is moving and who
is observing!
Check Point #1 Review
 Since velocity is a vector quantity, rules
of vector addition and vector resolution
apply
 If vectors go in the same direction:
ADD!
 If vectors go in opposite directions:
SUBTRACT!
Motion Graph Trends
X= Displacement vs time graph
V= Velocity vs time graph
A= Acceleration vs time graph
Check Point #1 Review