What shape is a projectile's path through the air?
A ball leaves a cliff edge horizontally. A good sketch of its flight shows more than the curve. At each marked point, it shows the ball's velocity, split into its two component arrows.
The curve itself is the parabola. At any point on it, the ball's velocity has a horizontal component and a vertical component, drawn as two arrows, exactly as you have drawn components before.
Mark a few points on the arc: one at the launch, then points at equal time steps, say one second apart.
At every point, draw the same horizontal arrow. The horizontal velocity never changes, so every horizontal arrow has the same length.
At the launch point, draw no vertical arrow. A horizontal launch starts with zero vertical velocity, so the launch point takes only a dot marked v_y = 0.
At each later point, draw a longer vertical arrow, pointing down. The vertical velocity grows by 9.8 m/s in every second of free fall, so the arrow grows by the same amount each second.
A ball rolls off a cliff edge at 6 m/s. Describe the component arrows a correct sketch shows at the launch, after 1 s, and after 2 s.
At the launch: a 6 m/s horizontal arrow and no vertical arrow, only the v_y = 0 dot.
After 1 s: the same 6 m/s horizontal arrow, and a 9.8 m/s vertical arrow pointing down.
After 2 s of free fall, the vertical velocity is 2 × 9.8 = 19.6 m/s.
So after 2 s: the same 6 m/s horizontal arrow, and a 19.6 m/s vertical arrow, twice the 1 s arrow.
Equal 6 m/s horizontal arrows; vertical arrows of 0, 9.8, and 19.6 m/s.
A sketch of a ball's flight off a ledge marks the launch point and two later points. How does the horizontal arrow at the last point compare with the horizontal arrow at the launch?
A sketch of a marble's flight off a counter shows vertical arrows at several points. How do the vertical arrows change from point to point as the marble falls?
A dart leaves a shelf horizontally. Which arrows belong at the launch point of a correct sketch?
A correct sketch of a ball's flight off a roof marks points one second apart. Between one marked point and the next, what happens to the vertical arrow?
A student sketches a stone's flight off a sea wall, marking points at equal time steps from the launch to the water. At which marked point is the stone's vertical arrow longest?
Four sketches show the same ball's flight off a cliff, with component arrows at several marked points. Which description matches a correct sketch?