Two parallel wires carrying current push on each other without touching: each wire sits in the magnetic field the other one makes, so each feels the motor effect force. Currents in the same direction pull the wires together, opposite currents push them apart - and the force per metre, F/l = (mu0/2pi) I1I2/r, was measured so precisely it once defined the ampere itself. This is the real knowscape from knowhere, not a picture of one. Drag it. Watch what actually changes.
Put a current where a magnetic field lives and the wire gets shoved — always at right angles to both. That one sideways push is the whole topic: it sets the force on a wire, and since every wire makes its own field, two wires shove each other hard enough to define the ampere.
In still water you drift, no sideways pull, nothing pushing you off line.
A rip runs across your path — the faster it flows, the harder the tug.
Stronger flow, stronger field, wider crossing — the sideways force climbs together.
knowhere maps every concept to what it rests on and what rests on it — 1 underneath this one, 0 built on top. Each one says why, in a sentence, not as an arrow on a diagram.
Each one is its own knowscape in the app — built for how a particular student takes things in, not one explanation handed to everybody.
Every HSC and VCE concept in knowhere is built like this one — mapped to your curriculum, never capped by it. Free for a week. No card tricks, no lecture.
Free for a week, then $49 once — the 2026 exam pass ends itself after the last exam. 0 days of the pass left.
Free for a week, then a plan you can stop any time.
not your card? send it to whoever's is.