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Projectile Motion Linear Motion, Free Fall, and Vectors Combined! Projectile Is any object that moves through air or space acted on only by gravity (2 dimensional motion) Projectiles If a bullet is shot out of a gun horizontally and another is dropped from the same height, which will hit the ground first? Why? Components of Projectiles (Vectors!) Horizontal Component (x-direction): no forces, constant velocity, no acceleration Vxo = Vx ax = 0 Components of Projectiles (Vectors!) Vertical Component ( y- direction) : force of gravity, velocity changes, acceleration ay = -9.80m/s2 Components are INDEPENDENT The components do not depend on each other Combined, they form the projectiles path (its TRAJECTORY) Time is the only factor that is the same in both directions Target Practice If I were to shoot at a target, where should I aim? Components of a projectile’s velocity For a vertically launched projectile, the shape of the trajectory is a parabola: Did you get it? How do horizontal and vertical motion effect each other in projectile motion? Describe the velocity and acceleration in the x direction. Describe the velocity and acceleration in the y direction. Solving problems Both horizontal and vertical motions are constant acceleration so the old eq. of motion still apply! x-component y- component v= vo + at d= do+vot+1/2 at2 v2=v2o + 2a(d-do) Practice Problem You decide to go cliff jumping and run off a 10.0 m cliff with a horizontal velocity of 1.50 m/s. How far from the bottom of the cliff will you land in the water?