70 likes | 219 Views
PROJECTILE MOTION. Basic Facts. First described by Galileo Description made by analyzing horizontal and vertical components separately Assumes NO AIR RESISTANCE!. Definitions. Projectiles: objects launched Trajectory: the path that projectiles follow
E N D
Basic Facts • First described by Galileo • Description made by analyzing horizontal and vertical components separately • Assumes NO AIR RESISTANCE!
Definitions • Projectiles: objects launched • Trajectory: the path that projectiles follow • Range: the maximum horizontal displacement • Height: the maximum vertical displacement
Facts about Projectiles • Horizontal velocity is constant • Vxi = Vxf • Use the big four equations from constant acceleration (use a = g in vertical case) • An object projected horizontally will reach the ground in the same time as an object dropped vertically
Projectiles Launched Horizontally • A rock is thrown horizontally from a 100.0 m high cliff. It strikes level ground 90.0 m from the base of the cliff. At what speed was the rock thrown? • Sketch • Identify your knowns and unknowns • Pick your equations and modify • Solve
Projectiles Launched at an Angle • Height occurs at ½ time • Angle of launch should be incorporated into equations
Sample #2 • A football is kicked at an angle of 37 degrees with a velocity of 20.0 m/s. Calculate: the height, the time of travel before it hits the ground, how far away it hits the ground, the velocity vector at the height, and the acceleration vector at the height. Assume for simplicity that the ball leaves the foot at ground level.