2. Projectile Motion Free fall with an initial horizontal velocity
Follows a parabolic trajectory
An object dropped and an object given an initial horizontal velocity will reach the ground at the same time!!
Myth Busters Video
Roadrunner Physics Misconception

3. Points to Remember: Simplifying Problems
No horizontal acceleration: ax = 0
Constant horizontal velocity: vxi = vxf
Vertical Acceleration = g = -9.8 m/s2
Time for horizontal = Time for vertical
Simplifying Problems
In this class we will not calculate values for projectiles with an initial vertical velocity: vyi = 0
Kinematic equations simplified to:

4. Simplified Projectile Equations
Horizontal Equation
Vertical Equations

5. vx = initial horizontal velocity
Object Launched Horizontally
vx = initial horizontal velocity
Δy = initial height
above ground
t = total time in the air
Δx = horizontal range

6. Concept Check
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7. Object Launched at an Angle
vi = initial velocity
q = launch angle
Δy = maximum height
t = total time in air
Δx = horizontal range
*Maximum range is accomplished with a 45° angle

8. Concept Check
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9. Concept Check
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10. Solving Projectile Problems
Completely separate x and y components
Use this table and fill it out:
ax is always 0
ay is always -9.8 m/s2
vxf is always the same as vxi
Vyi is always 0 in this class
Must first solve for time (using kinematic equations)
Use time to solve for other unknown
X (Horizontal)
Y (Vertical)
Δx =
vxi =
vyi = 0
vxf = vxi
vyf =
ax = 0
ay = -9.8 m/s2
t = ?

11. Practice Problem
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