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Free fall. Objects that fall under the influence of gravity and are heavy enough to neglect air resistance . The speed of the ball increases 9.8m/s every second because g = 9.8m/s 2. v t.
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Free fall Objects that fall under the influence of gravity and are heavy enough to neglect air resistance.
The speed of the ball increases 9.8m/s every second because g = 9.8m/s2 • v • t
Falling from rest • d • t
What does motion map of object being thrown upward look like?
A juggler is juggling two oranges on the top of a high wire. One orange he throws downward at a speed of 1.5 m/s and one he throws upward at a speed of 1.5 m/s. Which orange will hit the ground first? Which orange will have a faster speed right before hitting the ground?
Free fall where the earth is the reference point Position vs time Velocity vs time
Comparing earths and the moons Free fall • Moon g = 1.6 m/s2 • Thefirst second • The ball has fallen • .8 m and at 1.6 m/s2 • After three seconds the • ball has fallen 7.2m • and is moving at a speed of 4.8 m/s • Earth g = 9.8 m/s 2 • The first second • The ball has fallen • 4.9 m • And is moving 9.8 m/s • After three seconds • The ball has fallen 44.1m and is moving at 29.4m/ s
An object falls from rest for 10 seconds • A. What is its final velocity? • B. How far has it fallen?
An object is thrown upward with a speed of 15 m/s on the surface of the moon where the acceleration due to gravity is 1.6 m/s2 • A. What is the maximum height reached by the object? • B. How long does it take for the object to reach its maximum height? • C. How long does it take for the object to return to where it was thrown? • D. What is the object’s speed after 2.0 seconds?
A bullet is shot straight up on earth and returns to its starting point in 4.8 seconds. What is the speed of the bullet?
Effects of air resistance (Drag) • Acceleration decreases to zero • Velocity reaches a constant velocity called Terminal velocity. • Video 1 • Video 2