Graphing the Path of a Projectile- “GRAPHED PATH” Let’s graph the path a ball takes when it is kicked horizontally of a cliff 80 m high at 10 m/s. How long does it take the ball the reach the ground?   d = vit + ½ at2 d = ½ at2 2 2   a a t2 = 2d a     t = 4 s

t (s) dx (m) dy (m) vx (m/s) vy (m/s) v (m/s)

Now we need to fill information into this data table: 1. Horizontal velocity doesn’t change a = 0 5. Resultant of vx and vy 2. dx = vxt 4. d = vit + ½ at2 3. vfy = viy + ayt t (s) dx (m) dy (m) vx (m/s) vy (m/s) v (m/s) 10 10 1 10 -5 10 -10 14.14 2 20 -20 10 -20 22.36 3 30 -45 10 -30 31.62 4 40 -80 10 -40 41.23 vx a2 + b2 = c2 vy v

Plotting all of this info on the graph can be tricky. Remember this: These 2 columns are going to be points on the graph. These 3 columns are going to be vector arrows on the graph. t (s) dx (m) dy (m) vx (m/s) vy (m/s) v (m/s) 10 10 1 10 -5 10 -10 14.14 2 20 -20 10 -20 22.36 3 30 -45 10 -30 31.62 4 40 -80 10 -40 41.23 Graphing the path of the projectile needs to be a scaled drawing. Assign a scale and use a ruler to draw out vectors. Also use different colors for the vx and vy vectors. 1 cm = 5 m/s

points vectors t (s) dx (m) dy (m) vx (m/s) vy (m/s) v (m/s) 10 1 -5 -10 14.14 2 20 -20 22.36 3 30 -45 -30 31.62 4 40 -80 -40 41.23