3D Galvanometer 2
This second galvanometer model focuses on how the instrument detects very small currents. Explore the coil, magnet and spring in 3D and see how the motor effect converts a current of a few microamps into a deflection you can read off a scale.
How to use this simulation
- Feed different current values into the coil
- Orbit the 3D model to view it from any angle
- Adjust coil turns and spring stiffness
What to look for
- Very small currents still produce a readable deflection
- A weaker restoring spring gives a larger deflection for the same current
- The pointer returns to zero when the current is switched off
The physics behind it
Each side of the coil carries current perpendicular to the magnetic field and experiences a force F = BIL. With N turns those forces produce a torque BIAN that twists the coil until the hairspring's restoring torque matches it. Sensitivity is improved by increasing N, increasing B, or using a weaker spring.