{"id": "card_n_6f5aa0b22245", "kind": "note", "title": "Capacitor — the exponential clock (RC time constant)", "body": "A capacitor charging through a resistor follows V(t) = V·(1 − e^(−t/RC)); after one\ntime constant τ = RC it holds exactly 1 − 1/e ≈ 63.2% of the supply — sealed in-domain\n(1000 Ω × 1000 µF = 1 s; 5 V → 3.1606 V at t = 1 s): https://narrowhighway.com/s/1ee0d3ed486453eee0967146a531984888709198b39fb16a7b2c2a5f58ef1b73 . Every timer, filter, and\ndebounce circuit is this one exponential wearing different values. Real parts add leakage\nand ESR — empirical, not sealed.", "source": {"label": "Concordance assay — 2026-07-09", "url": "https://narrowhighway.com/s/1ee0d3ed486453eee0967146a531984888709198b39fb16a7b2c2a5f58ef1b73", "ref": "electronics_dig", "authority_tier": "engine_derived"}, "shelf": "science", "box": "electronics", "bands": ["capacitor", "rc time constant", "exponential", "electronics", "timer", "filter"], "connections": [], "author": "engine", "created_at": "2026-07-10T00:59:49.508624+00:00", "updated_at": "2026-07-10T00:59:49.508624+00:00", "visibility": "public", "lifecycle_stage": "public", "volatility": "permanent", "surface": "secular", "metrics": {"paperclips_count": 0, "helpful_count": 0, "not_helpful_count": 0, "cite_count": 0, "walks_through_count": 0, "flagged_count": 0}, "source_hash": "5b63ac0d270b74d0e1a6b409278cb7fc50bb353191decf0697ba2f255c4d0fe6"}