How to play Force Table
- Choose a table and read each string's force and angle.
- Split each force into components: Fₓ = F cos θ and F_y = F sin θ.
- Set your string so that its components cancel the sum of the others.
- Release the ring. It stays still only if the vector sum is (almost) zero.
Adding forces as vectors
Forces are vectors, so they add tip to tail, not by adding their sizes. The sum of sizes Σ|F| is a scalar and never tells you whether the ring moves. Only the vector sum ΣF matters: when it is zero, the ring is in equilibrium. The size of a sum is never larger than the sum of the sizes.
A focused learning model
The ring has a mass of 0.2 kg and rests on the table. Static friction holds it while the net string force is at most 0.05 N; above that it slides, against 0.04 N of sliding friction, until it reaches the stop pin 4 cm from the centre. String directions are treated as constant over that small distance. Playback runs 10 times slower than real time.