Gemology Notes vs PhysicsBench

Systematic Gemology Notes An offline reference app dedicated to gemology learning, covering the fundamental properties, crystal structures, and systematic classification of common gemstones. KEY FEATURES • Gemstone Browser — Reference material organized by crystal system and gemstone species • 3D Crystal Models — Interactive displays of each gemstone's crystal structure; rotate and zoom to examine every angle • Detailed Notes — Systematic knowledge covering physical properties, optical characteristics, and key identification points • Fully Offline — No internet connection required; study anywhere, anytime Ideal for gemology students, professional gemologists and appraisers, jewelers, and collectors.

Solve real physics, not fake wiring puzzles. PhysicsBench simulates actual circuits, light paths and torque — then shows you the formula behind your solution. Wire a battery, close a switch, watch current flow and a bulb light up. Bounce a beam off mirrors into the target. Balance a lever with the right weights. Every level ends with a Principle Card: the law, the formula, and your level's real numbers substituted in. MAIN FEATURES • 108 levels across seven subjects: Circuits, Optics, Mechanics, Dynamics, Electromagnetism, Heat & Fluids, Waves & Sound • Three difficulties per subject: Intro, Core, Brainer • True simulation — nodal analysis for DC circuits with diodes and capacitors, ray tracing for light, torque balance, and closed-form models for motion, induction, heat and sound • Principle Card after every solve, with your own values • Daily experiment with streaks • Courses by topic, a review queue for levels you needed hints on, and a mastery radar • Unlimited hints, never a consumable • Import and play levels friends share as a code or .physlab file • Home-screen widget, Apple Pencil notes and bench recording • Works fully offline. No ads, no accounts, no tracking PRO — ONE-TIME PURCHASE • All 108 levels, including every Brainer level • Full step-by-step derivation on every Principle Card • Frame-by-frame replay with velocity and force arrows, and a draggable RC charging curve • Free Bench lab: sliders for every model, plus building, naming and saving experiments • Level editor that proves your puzzle is solvable before you share it • Full probe panel: per-branch voltage, current and power; every beam path; torque breakdown • Four extra themes and three alternate app icons • Future local Pro levels in this app ANSWER REPORTS — OPTIONAL Stuck? Unlock the worked answer for a difficulty with a separate one-time purchase: the solved bench, every move with its reason and the principle worked through. Not included in Pro; hints stay free. PRIVACY Everything runs on your device. Progress syncs through your own private iCloud. No account, no analytics SDK, no data sent to us. NOTE Levels use teaching-simplified models (ideal wires, batteries with internal resistance, single-colour rays). The in-app "About the model" page lists every assumption. Support · Privacy Policy · Terms of Use are in Settings.