Free Fall

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

11. 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 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?

12. 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 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?

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 Steps 1. multiply dv times 2 2. divide by g 3. Press = 4. Press the square root button