One-Prompt Physics: Riftrunner Simulates a 10kg Ball vs 10kg Cotton Drop

Prompt: “A 10kg ball and 10kg of cotton drop simultaneously from 100 meters.” Riftrunner on LMArena turned it into a clean science visual in one go.

Gravity demo: equal mass, different density, same drop height.

Why this is interesting

• Physics intuition: mass is equal, drag differs; outcome depends on air resistance, not weight alone.


• Rapid science visualization: one prompt produced a usable clip for teaching/demo.


• Consistency: riftrunner kept camera, timing, and scale coherent through the fall.

What riftrunner did well

• Ground plane & scale: clear 100m context avoids “floating” artifacts.


• Motion clarity: cotton shows drag-influenced descent; ball stays ballistic.


• Framing: neutral background makes the physics point, not the styling.

How to prompt for similar science clips

• State masses, materials, height, and camera framing in one sentence.


• Add one constraint about timing (“full fall in N seconds”) to keep pacing steady.


• Prefer neutral lighting/background so the motion is the focus.

Bottom line

Riftrunner on LMArena makes fast physics explainers practical: one concise prompt yields a teaching-ready video that spotlights gravity, drag, and mass intuition without manual editing.