4 A History of Projectile Motion Aristotle:The canon ball travels in astraight line until it lost its‘impetus’.Galileo:- a result of Free Fall Motionalong y-yaxis and UniformMotion along x-axis.
5 Projectile Motion = Sum of 2 Independent Motions 1. Along x, the projectile travels with constant velocity.vx=vxo x = vxotAlong y, the projectile travels in free-fall fashion.vy = vyo – gt y = vyot – (1/2) gt2 , g= 9.8 m/s2Projectile motion = a combination of uniform motion along x anduniformly accelerated motion (free fall) along y.
6 What’s the similarity between a freely-falling ball and a projectile ? uniform motionProjectilemotionverticalmotionxA dropped ball falls in the same time as a ball shot horizontally.Along the vertical, their motions are identical (uniformlyaccelerated motion (free-fall).Along the horizontal, notice the ball fired horizontally covers theSame distance in the same unit time intervals (uniform motion along x)
7 v vy vx Velocity Components at various points of the Trajectory vertical componentvyvNet velocityvxHorizonal componentAbove: Vectors areadded in geometricFashion.Launch speed = Return Speed.Speed is minimum at apex of parabolic trajectory.
8 At what angle do I launch for Maximum Range ? Need to stay in air for the longest time,and with the fastest horizontal velocity componentAnswer: 45°
9 Everyday Examples of Projectile Motion Baseball being thrownWater fountainsFireworks DisplaysSoccer ball being kickedBallistics Testing