We attach a high-quality bearing hub with a 15cm diameter wheel to a substantial table clamp. One end of a metal rod is firmly attached to the hub, the other end is fixed into a second table clamp. A slotted mass hangs from the steel cable wrapped around the wheel. Using the degree scale and vernier arm mounted on the wheel, you can measure the angle of the twist the torque applies to the rod up to 100° of rotation precisely to 0.1 degree of rotation. The apparatus comes with four precision-milled, 1m-long rods three steel and one brass fitted with bushings. The thinnest rod also has a bushing near the middle that you can clamp onto the table socket, providing an effective length of 50cm. Also includes clamp and complete operating instructions. Requires slotted masses, available separately.
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