Simple d.c. motor sim
A coil of 40 turns sits in a field of 0.1 T between the poles.
Simple d.c. motor · covers the GCSE, IGCSE, O-Level topic
What the sim shows
A coil of 40 turns sits in a field of 0.1 T between the poles. Current in each long side is at right angles to the field, so each side is pushed with F = BIL × N: one side up and the other down, which turns the coil. The push stays the same size, but its turning effect is largest when the coil is level and falls to zero when it is upright. Just there the brushes cross the gaps in the split ring, so the current in the coil reverses every half turn and the coil keeps turning the same way. Tap the switch (or press R) to send the current the other way round: the coil turns backwards. Space switches it off. Shown slowed down.
- The coil, and the current flowing in it
- Split ring and brushes: they swap the current every half turn
Use it in your lessons
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