1. IB Physics 11 Mechanics 2.1 Projectiles 1 Mr. Jean

2. The plan: Video clip of the day –http://www.youtube.com/watch?v=gQef06srB eQhttp://www.youtube.com/watch?v=gQef06srB eQ Free fall Basic Projectiles

3. Slide which is out of order!

4. This is also out of place:

5. Free Falling Objects: When an object is dropped. –1) There is NO account for air resistance. –2) All Free-Fall objects fall at the same rate

6. Demonstration: Textbook vs. Piece of paper Strobe Light and water droplets Water no gravity –http://www.youtube.com/watch?v=ntQ7qGilqZ Ehttp://www.youtube.com/watch?v=ntQ7qGilqZ E

7. Example: A ball is dropped from the top of CN tower which is 440m above ground. The acceleration of gravity is -9.81m/s 2. –A) How long does it take for the ball to hit the ground? –B) At what velocity does it hit the ground?

8. A) How long does it take for the ball to hit the ground?

10. B) At what velocity does it hit the ground?

12. Projectile Motion:

14. MIT Monkey: http://www.youtube.com/watch?v=MkKEwr shYWshttp://www.youtube.com/watch?v=MkKEwr shYWs

16. X - component: Initial velocity in x? Final velocity in x? Final displacement in x?

17. Y - component: Initial velocity in y? Final velocity in y? Final displacement in y?

18. Example projectile question: A ball is hit off the ground at 53 degree angle of elevation. Initial velocity is 30m/s. Assume the surface is level. –A) When does the ball reach maximum height? –B) How long was the ball in the air? –C) How far did the ball go (range)?

19. Max Height:

22. How long was the ball in the air?

24. Range?

26. An object on Earth is moving at 400m/s. It is launched at a 25 degree angle. –How long (in seconds) was it in the air? –What was the total range of this projectile?

30. Projectile Questions: Try the two projectile questions Projectile Lab will be done on Thursday likely.