Free Fall Object is always going straight up or straight down. (The horizontal velocity is zero.) Acceleration for all these problems is g (--9.81 m/s2). A dropped object has an initial velocity of zero. (vi = 0 m/s) A thrown object has a non-zero initial velocity. (vi ¹ 0 m/s) Note the sign

Free Fall Velocity has a direction. Up is positive and down is negative. The velocity at the top of the flight is zero. The time to get to the top = the time to fall to the initial level. The final velocity is equal in magnitude and opposite in direction to the initial velocity ONLY if the object starts and stops at the same height.

Free Fall & Motion Equations Vavg = d/t Vavg = (vi + vf)/2 a = (vf - vi)/t Same equations just combined and rearranged to solve for different variables. For these problems: a = g First equation just rearrange acceleration to solve for final velocity. Second equation, substitute equation for final velocity into v average and set equal to d/t and solve for d. (eliminates vf) Third equation, solve acceleration for time and substitute into v average and set equal to (vi+vf)/s and solve for vf2. (eliminates time) vf = gt + vi if vi = 0, vf = gt d = vit + .5gt 2 if vi = 0, d = .5gt 2 vf2 = 2gd + vi2 if vi = 0, vf = 2gd

A coconut falls out of a tree and it is in free fall for 2 seconds, how tall is the tree? How fast is it moving when it hits the ground? Given U Equation Substitute Solve 2 seconds d = ?

A couple of two step questions A ball starts from rest and rolls 50m at a constant rate of acceleration. What is it’s speed after 10s? A car races down a 200m drag strip. At the finish line, the car’s final velocity is 50m/s. What is the average rate of acceleration?

Free Fall We’re going to determine how far Jake Brown fell (he ended up with only minor injuries) https://www.youtube.com/watch?v=CTeXKHkNqgk YouTube video is 26 frames per second…his peak was at 15.73 s and he first strikes the ground at 17.38 s How far did he fall?  I've got a fracture in one of my vertebras, but it's pretty minor. He also sustained bruises to his liver and lung, and a mild concussion. The liver injury is what's keeping him under watch at California Hospital Medical Center in downtown Los Angeles. wrist injury is a small bone fracture. 13.3 m = 44 feet which is about 4 ½ stories.

Free Fall YouTube video is 26 frames per second…his peak was at 15.73 s and he first strikes the ground at 17.38 s How far did he fall?  I've got a fracture in one of my vertebras, but it's pretty minor. He also sustained bruises to his liver and lung, and a mild concussion. The liver injury is what's keeping him under watch at California Hospital Medical Center in downtown Los Angeles. wrist injury is a small bone fracture. 13.3 m = 44 feet which is about 4 ½ stories. Given Unknown Equation Substitute Solve