1. The Kinematics Equations (1D Equations of Motion)
Unit 2 Class Notes
The Kinematics Equations (1D Equations of Motion)
Accelerated Physics

2. Throw-Ups, Come-Downs, Throw-Downs
Day #4
Throw-Ups, Come-Downs, Throw-Downs

9. To solve for “t”, use the quadratic formula 1 2
UP +, DOWN -
a = -9.8 m/s2
v2 = 0 (at the top)
v1 = 20 m/s
a = -9.8 m/s2
v2 = 0 m/s
To solve for “t”, use the quadratic formula 

10. 2 1 3
UP +, DOWN -
a = -9.8 m/s2
Dt12 = Dt23
v2 = 0 (at the top)
v3 = -v1
Two VERY important things to know about the case where you throw an object up and catch it at the same height.

11. #2 2 v2 = 0 m/s v2 = 0 m/s 3 a = -9.8 m/s2 a = -9.8 m/s2 1 Dx = 30 m
Due to the fact that the ball is thrown and caught at the same height …

12. #2 1 2 4 3
v1 = m/s
a = -9.8 m/s2
Dx = -1 m
To solve for “t”, use the quadratic formula 
Only positive times make physical sense

13. #3
A man launches a popcorn ball straight up into the air. It reaches its peak, and then begins to fall back to the ground. 4 seconds after it was released from the man’s hand, a bird catches the ball 20 ft above the ground. What was the velocity at which the ball left the man’s hand?
Dt = 4 sec
a = ft/s2
Dx = 20 ft