# Kinematic/Free Fall Tommy Myszka Nick Sraga Mike Jewell.

## Presentation on theme: "Kinematic/Free Fall Tommy Myszka Nick Sraga Mike Jewell."— Presentation transcript:

Kinematic/Free Fall Tommy Myszka Nick Sraga Mike Jewell

Terms Speed – distance traveled in a period of time Velocity- distance traveled in a period of time in a certain direction Instantaneous velocity – how fast you are traveling at a particular time Acceleration – change in velocity over time

Equations speed = distance time acceleration = V F -V I time velocity = displacement time Other important equations V F 2 -V I 2 = 2ad ½ at2 + V I t = d

Concepts Initial speed always must be zero Gravity equals -9.8 m/s/s Free fall acceleration equals –9.8 m/s/s As you free fall, your distance per second increases, as does your velocity per second

Examples From the Real World #1 Skydiving As you skydive, you’re free falling toward the earth at – 9.8 m/s/s

Examples From the Real World #2 Rain As the falls it is constantly getting itself a bigger and bigger velocity towards the earth

Sample Question #1 A ball dropped from rest picks up speed 10 m/s. After it falls for 4 seconds, how fast is it going? Givens A=10m/s T= 4sec Equation: a=V F -V I T 10m/s=V F -0 4 40=V F Answer: 40 m/s

Sample Question #2 A ball is thrown straight down with an initial speed of 20 m/s. After 3 seconds how fast is it going? Givens V I =20m/s t=3 sec a= -9.8m/s 2 Equation: a=V F -V I T -9.8=V F -20 3 29.4=V F -2049.4=V F Answer: 49.4m/s

Sample Question #3 You shoot an arrow straight up at 50m/s. When will it hit the ground? Given V F =0 V I =50m/s a= -9.8 Equation: a=V F -V I T -9.8=0-50 t -9.8t = -50 t= -50 -9.8 Answer: 5.1

Sample Question #4 Wieldy Coyote runs off a 100 meter cliff while chasing the Roadrunner. He begins to freefall. What is his velocity when he hits the ground? Given D=100m a=-9.8 V I =0 Equation: V F 2 -V I 2 =2ad V F 2 -0=2(9.8)100V F 2 =1960 V F = 44.2 Answer: 44.2

Quiz Questions #1 A bullet fired horizontally at 650m/s. How far will it go in 1.1 seconds? Answer: 715m #2 A base ball is hit straight up to a height of 40 meters. How fast was the ball moving when it let the bat? Answer: 28 m/s

Quiz Questions #3 If a skydiver jumps out of an airplane, and his shoot failed and hits the ground at 50m/s. How high was he when he jump? Answer: 127.5 meters #4 If a person jumps off a 15 meter cliff into water. What is the persons velocity when he hits the water? Answer: 17.15m/s