1. Free Fall Objectives 1.) define free fall
2.) explain that all falling objects accelerate
3.) agree that all objects fall at the same rate
4.) write the free fall equations

2. Free Fall

3. Introduction Free Fall • motion caused only by gravity
• all objects fall at the same rate
- works in a vacuum: area with no air
- ignores air resistance
Acceleration Due to Gravity
is a constant.
is called g
is = 10 m/s2 on surface of earth
is different on the moon, but still constant

4. Free Fall Equations Key
vv= vertical velocity (in m/s)
dv = vertical distance (in meters)
g = acceleration due to gravity (10 m/s2)
t = time (in seconds)

5. Vertical Velocity Equation

6. Vertical Distance Equation

7. Time to Fall Equation

8. One more free fall

9. Worksheet A Free Fall Equations

10. 1.) How fast will a ball be traveling if it falls for 5 seconds?
t = 5 seconds
g = 10 m/s2
• vv = gt
vv = 10(5)
vv = 50 m/s
Data
Equation
Math
Answer

11. 2. An apple falls out of a tree and takes 1
2. An apple falls out of a tree and takes 1.75 seconds to strike the ground. How high was the apple from the ground?
Data
Equation
Math
Answer
t = 1.75 seconds
g = 10 m/s2
dv = 0.5gt2
dv = 0.5(10)(1.75)2
dv = 0.5(10)(3.06)
dv = 0.5(30.6)
dv = 15.3 m

12. Data dv = 1000 m g = 10 m/s2 Equation • t = √2dv/g Math
3. A plane drops a C.A.R.E. package to some needy people in the jungle from a height of 1000 m. How long will it take the package to strike the ground?
Data
Equation
Math
Answer
dv = 1000 m
g = 10 m/s2
• t = √2dv/g
t = √2(1000)/10
t = √2000/10
t = √200
t = 14.1 seconds

13. Free Fall Equations Key: vv= vertical velocity (in m/s)
dv = vertical distance (in meters)
g = acceleration due to gravity (10 m/s2) t = time (in seconds)
 Vertical Velocity
Steps
1. Multiply g times time 
Vertical Distance 
  Steps
1. Square time (multiply by itself)
2. Multiply by g
3. Multiply by 0.5
Time to Fall 
1. multiply dv times 2
2. divide by g
3. Press =
4. Press the square root button