1. Physics Section 3.3 Properties of Projectile Motion
Consider the paths of two balls. The first (gray)is dropped from rest and the second (black)is given an initial horizontal velocity. Both balls drop same distance in each time interval as indicated by the horizontal lines.
 They both have the same vertical velocity vy = g(Δt) and they hit the ground at the same time. The black ball also has a horizontal velocity component, vx which causes it to follow a curved path.

2. A rifle bullet fired horizontally will strike the ground at the same time as a bullet dropped from the same height at the same time.
Example: A ball is thrown horizontally from a height of 2.0 m and it strikes the floor at a point 15 m east. Find the velocity at which the ball was thrown.

3. example
Example: A baseball rolls off a .70 m high desk and strikes the floor .25 m away from the base of the desk. How fast was the ball rolling?

4. Student problem
A airplane is flying at a speed of 250 m/s in level flight. It drops a package from a height of 450 m. How far does the package travel horizontally before it strikes the ground?

5. When an object is projected upward at any angle other than vertical, its path is parabolic if air resistance is eliminated. Projectile motion is the curved path that an object follows projected near the surface of the Earth.
Note: The vertical velocity vy = 0 at the top of the projectiles trajectory.
The vertical acceleration is always -9.8 m/s2.
The horizontal velocity vx is constant.
The time the projectile spends traveling up is equal to the time it spends falling.

6. problems
A bullet is fired at a velocity of 350 m/s at an angle of 35 degrees from the horizon. How long is it in the air? How far does it travel?

7. Student problem
A stuntman needs to drive a car up a ramp at a 25 degree angle while traveling 50.0 m/s and flies through the air and land on a similar ramp. How far should the second ramp be placed from the first ramp?

8. assignment
Page 101
Section review problems 1,2,3 and #3 in practice E