1.1 Motion and Motion Graphs
Kinematics is the study of motion without
considering the forces that produce the motion.
Dynamics is the study of the causes of motion
Scalar: A quantity that has
magnitude (size) but no direction
Vector: A quantity that has both
magnitude (size) and direction.
Distance (d)-the total magnitude of
movement of an object.
Position (d)-the straight-line distance
and direction of an object from a
reference point.
Displacement (^d) the change in
position of an object
Speed (Vav) the total distance travelled
divided by the total time to travel that
distance
Average Velocity (Vav) the total
displacement divided by the time
interval for that change; the slope of a
secant on a position-time graph.
Position-time graph of
a runner’s motion
Velocity-Time graph of
a runner’s motion
Instantaneous velocity- the velocity of an object at a certain instance of
time. This is calculated by drawing a tangent at a certain instance of time.
Tangent is a straight line that touches a curve at a single point and has
the same slope as the curve at that point
Acceleration -the rate of change of
velocity
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Average acceleration (aav) is the change in
velocity divided by the time interval for that
change.
Instantaneous acceleration is the acceleration at
a particular instant in time. This is equal to the
slope of the velocity-time graph at a particular
instant in time.
Graphing motion with constant
acceleration
Velocity Time Graph
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What does the slope of the line represent?
What does the area under the line represent?
Acceleration-time Graph
REVIEW: d-t vs. v-t graphs
d-t graph
v-t graph
Position
Avg. velocity
Instantaneous
velocity
Avg. acceleration
Slope of tangent
line
Instantaneous
velocity
Instantaneous
acceleration
Area between the
x-axis and the
graph
Nothing
displacement
Point on the
graph
Slope of secant
line (a line that
intersects two points on
the graph)
Converting graphs
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Displacement-Time graph
Velocity-Time graph
Acceleration graph
1.2 Equations of Motion
One-Dimensional Motion with Constant Acceleration
In order to solve problems with displacement, the average
acceleration formula can be rearranged in many ways
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These equations are used to solve problems with
constant acceleration