A plotting compass lines up with the magnetic field wherever it sits, its red end pointing the way a free north pole would be pushed. Drag the compass anywhere to explore. Drag the middle of the magnet to move it, or drag near an end to turn it. Each round marks a point P: predict which way the red end will point there, then place the compass to check. Switch on the field lines, or sprinkle iron filings, to see the whole pattern.
MissionPredict which way the compass needle points at the marked point P.Round 1Streak 0Best 0
Red end points:
needle (red end) pointsdrag to explore
field strength at the compasslow
point P resultnot placed yet
The direction of the field at a point is the direction of the force on a N pole there. Field lines leave the N pole, curve round to the S pole, and crowd together where the field is strong.