1. August 29
AP physics

2. In:
A stone is thrown horizontally with an initial speed of 10 m/s from a bridge. If air resistance could be ignored, how long would it take the stone to strike the water 80 m below the bridge?
1 s
2 s
4 s
6 s
8 s

3. Objective: To use 2 dimensions to understand projectile motion.
Success criteria:
Be able to solve projectile problems with horizontal initial velocity

4. Projectile motion

5. Video: Snowmobile projectile
Preliminary run
I noticed:
Run 1
Run 2
Run 3

6. Horizontal and Vertical directions are independent.

7. Horizontal motion has constant velocity.

8. Vertical motion is freefall motion.

9. Divide and conquer!
Horizontal Vertical
Time crosses the line!

10. Practice:
A ball is kicked with a velocity of 20 m/s at an angle of 45o from horizontal.
What is the horizontal and vertical initial velocity?

11. How high will it go?

12. How far will it go?

13. A cannon shoots a cannon ball at 18m/s at an angle of 30o from the horizontal. What is the distance the cannonball goes?

14. Wiley Coyote slides horizontally off a 100 m cliff at 75 m/s
Wiley Coyote slides horizontally off a 100 m cliff at 75 m/s. How far from the base of the cliff will he land?

15. A bullet shoots from a gun at 200 m/s at an angle of 55o from the horizontal. How long is it in the air? How high will the bullet go? How far will the bullet travel.

16. A man jumps from a burning building 30 meters from the ground
A man jumps from a burning building 30 meters from the ground. His initial velocity is 10 m/s at 25o from the vertical. How long did it take him to land? How far away from the building should the firemen hold the net?

17. A tennis player hits a ball from 10 meters away from the net that just barely clears the .75 meter net. His initial velocity was 20 m/s. What was the angle he hit it with?

18. A diver jumps off the 10 meter platform with a velocity of 8 m/s at an angle of 55o from the horizontal. What were the horizontal and vertical components of her jump. How long does it take her to hit the water?

19. Out:
A stone is thrown horizontally with an initial speed of 30 m/s from a bridge. Find the stone’s total speed when it enters the water 4 seconds later.
30 m/s
40 m/s
50 m/s
60 m/s
70 m/s