Kinematics – Kinematic Equations
http://www.aplusphysics.com/courses/honors/kinematics/honors_kinematics.html
Unit #2 Kinematics

Objectives and Learning Targets
 Use kinematic equations to solve problems for
objects moving at a constant acceleration in a
straight line and in free fall.
 Resolve a vector into perpendicular components:
both graphically and algebraically.
Unit #2 Kinematics
Kinematic Equations
 These equations can help you solve for key variables
describing the motion of an object when you have a
constant acceleration. Once you know the value of
any three variables, you can use the kinematic
equations to solve for the other two!
Key Kinematics Variables
Variable
v0
v
Δx
a
t
Unit #2 Kinematics
Meaning
Initial velocity
Final velocity
Displacement
Acceleration
Time elapsed
Problem Solving Strategy

In using these equations to solve motion problems, it’s important to take care in
setting up your analysis before diving in to a solution. Key steps to solving kinematics
problems include:
1. Labeling your analysis for horizontal (x-axis) or vertical (y-axis) motion.
2. Choosing and indicating a positive direction (typically the direction of
initial motion).
3. Creating a motion analysis table (v0, v, Δx, a, t). Note that Δx is a
change in position, or displacement, and can be re-written as x-x0.
4. Using what you know about the problem to fill in your “givens” in the table.
5. Once you know three items in the table, use kinematic equations to
solve for any unknowns.
6. Verify that your solution makes sense.
(Note: these equations work for vertical and horizontal motion)
Unit #2 Kinematics
Sample Problem #1 – Horizontal Motion
Unit #2 Kinematics
Sample Problem #1 – Horizontal Motion
Unit #2 Kinematics
Sample Problem #2 – Vertical Motion
Unit #2 Kinematics
Sample Problem #2 – Vertical Motion
Unit #2 Kinematics
Sample Problem #3 – 2 Stepper
Unit #2 Kinematics
Sample Problem #3 – 2 Stepper
Unit #2 Kinematics
Sample Problem #4
Question: An astronaut drops a hammer from 2.0 meters above the surface of the
Moon. If the acceleration due to gravity on the Moon is 1.62 meters per second2,
how long will it take for the hammer to fall to the Moon’s surface?
Answer:
Unit #2 Kinematics
Create Your Own Problem
 Create your own Horizontal Motion Kinematics
Problem and solve it. Feel free to make it funny, but
keep it clean.
 Create a second problem making it vertical. Solve it
also.
 Trade with a neighbor and solve each other’s
problems before turning them in.
Unit #2 Kinematics