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Structure of mechanism |
| Function |
This device is composed of a graduated circular dial (the scale is from zero at the centre to 14) attached to a static stand, and a mobile part comprising a rectangular bobbin (Bakelite, enamelled copper wire) fixed to the stand by two twisted wires (upper and lower). The tension in these wires is adjusted via a screw comprising the upper attachment system. A protractor enables the measurement of the initial tension. The frame of the bobbin features a curved needle, which moves in front of a graduation to identify the position (torsion). Two terminals enable the electrical power to be connected. The fact that the device is large and that the wire has a low constant accentuates its sensitivity. |
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Application |
| Examples of application |
The presence of the bobbin on the mobile part, as well as the electrical connection, indicates that the device could have been used to study magnetic couples. It was used by future teachers during their studies at the men’s and women’s teacher training colleges, now the IUFM (University Teacher Training Institute) in Clermont-Ferrand |
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