Counterweight

How the Lever & Torque Physics Work

Counterweight is a physics puzzle about rotational statics and dynamic momentum. At the center of every stage rests a rigid balanced beam anchored upon a fulcrum pivot. Along the beam are numbered attachment hooks running from negative slots on the left to positive slots on the right. Placing a counterweight generates downward torque equal to its physical mass multiplied by its distance from the fulcrum.

The critical twist is that rolling marbles are not weightless passengers. As a marble rolls across the beam surface toward the goal basket, its mass continuously shifts outward, dynamically increasing its rotational leverage. A beam that begins in quiet equilibrium will tilt aggressively as soon as the marble crosses the midpoint. You must anticipate this shifting center of gravity, placing counterweights not just to hold the beam flat at rest, but to guide rolling momentum across gaps and over dangerous hazard spikes.

Beam Balance & Mass Controls

Position counterweights and control the physics simulation with straightforward mouse and keyboard interactions:

• Click / Drag Weights: Pick up weighted blocks (ranging from 1kg to 5kg) from the lower inventory rack and snap them onto beam hook slots.
• Spacebar: Releases the marble from its starting hopper to test your torque configuration, or advances to the next level when solved.
• P: Pauses the simulation during marble rollout so you can inspect velocity, beam tilt angle, and clearances.
• R: Resets the current trial, recalling the marble to its starting gate while leaving your counterweights in place for minor adjustments.
• N: Advances to the next unlocked puzzle after successfully depositing all marbles into the goal receptacle.

How to Beat Stage 5 (Taming the Dynamic Rebound)

Stage 5 introduces a divided beam with a central gap and a high-speed marble that shatters if it hits the far landing plate at a steep incline. The standard rookie mistake is loading heavy weights on the far right slot to tilt the bridge down before launch. While this levels the gap initially, the arriving marble adds its own weight to the right side, violently slamming the beam downward and launching the marble off the table.

The secret is counterbalancing for the marble's destination rather than its origin. Place a modest 2kg weight on slot -4 (left side) and a 3kg weight on slot +2 (right side). When the marble releases, the beam starts tilted slightly leftward, allowing smooth descent. As the rolling ball shoots across the central gap, its momentum tilts the right side down just in time to create a level runway directly into the goal basket.

Fulcrum Setups for Stages 4, 7, and 11

Higher stages incorporate moving fulcrums, dual rolling marbles, and hazard spikes requiring careful leverage math:

• Stage 4 (The Stepped Bridge): Avoid placing large masses on extreme edge hooks. Distribute medium 2kg weights across intermediate slots to prevent excessive tilt speeds that kick the marble into the overhead hazard.
• Stage 7 (Twin Marble Relay): Two marbles roll at staggered intervals. You must time beam equilibrium so the first marble tips the left wing down, climbs to the center, and transfers enough torque to tilt the second wing for the trailing ball.
• Stage 11 (Spike Chasm Gap): Requires a see-saw catapult effect. Hang your heaviest mass on slot -5, then drop a light 1kg weight on slot +1. The marble accelerates over the spikes before gravity has time to pull it down.

Beam Statics & Puzzle FAQ

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