Upload
alexis-cori-fitzgerald
View
216
Download
0
Tags:
Embed Size (px)
Citation preview
5 Minute Class StarterWrite this in your notes
Describe the motion of a falling object. • Does it have a
constant speed? • Does it have a
constant acceleration?
Physics 11Unit 1 Lesson 20
Star International AcademyMr. David Anderson
Today’s Agenda
1.Class Starter
2.Free Fall – free body diagram
3.Free Fall – mathematical formulas
2. Free Fall – Free Body Diagram
Free Body Force Diagram
What is a free body force diagram?
- A free body force diagram is a picture or a model showing the different forces acting on an object
Example: Pushing on a crate
Draw three free body diagrams
Beginning
of fall
Middleof fall
End of fall(no bounce)
Draw two free body diagrams
Sheet of paper
Balled up paper
Falling
Summary
Conclusion:
What forces are acting on a falling object?
Is a falling object accelerating? How do you know this?
PAUSE
Class Starter
Review the project description.
- Write down at least one question that you have about it.
3. Free Fall – Mathematical Model
Review of motion formulas
Velocity (speed) = change in position / change in time
a = d / t
Acceleration = change in velocity / change in time
a = v / t
Motion formula: constant speed
What is the acceleration?
a = 0
What is the velocity?
v = v0 (v0 = constant or initial velocity)
What is the position?
x = x0 + v0t
initialpositio
n
position change due to velocity
Bonus for Calculus students:
Start with the formula for position:
x = x0 + v0t
Differentiate implicitly with respect to time twice. Can you derive the other formulas?
Motion formula: constant acceleration
What is the acceleration?
a = a (a = constant acceleration)
What is the velocity?
v = v0 + at
What is the position?
x = x0 + v0t + ½at2
initialpositio
n
position change due to velocity
Bonus for Calculus students:
Start with the formula for position:
x = x0 + v0t + ½at2
Differentiate implicitly with respect to time twice. Can you derive the other formulas?
position change due to acceleration
Constant Acceleration Formula
x = x0 + v0t + ½at2
In math terms, what is the order of this formula?
If you graphed this formula, what is the shape of the graph?
Does this match your idea of free fall?
How does the formula change if the acceleration is zero?
Application to Projectile Motion
Projectile Motion
Projectile motion is a combination of motion types.
How does a projectile move in the horizontal (X) direction?
How does a projectile move in the vertical (Y) direction?