Torsion pendulum

Purpose of work is to study of laws of oscillations of the torsion pendulum.

Task: check up dependence of period of free oscillations torsion pendulum from its moment of inertia; check up a formula for the moment of inertia of ball (peg).

Devices and equipments: torsion pendulum, set of cylinders or pegs, balls.

Figure 14.1

The experimental setting (fig.14.1) consists of basis 1. In basis a peg is fastened 3, on what fix lower bracket 4 and overhead 13. On these brackets on a steel wire 16 the suspended scope 9, which has a moving slat 10 with two fixative nuts 11. In a scope on two centrings dowels 14 the probed body is fastened 15 (cylinder, peg, cube, ball) and it is compressed spirally 12. On a scope small flag is fastened 7, which, crossing the light ray of photoelectric sensor 8, includes the electronic system of count of amount oscillations (indicator 17) and stop-watch (indicator 22). After help of this small flag a scope of fix is in initial position of electromagnet 6 at certain corner of turn which is measured on a scale 5. On the front panel of device are: switches 18 – “Сеть'”, 19 – “Срос”, 20 “Пуск” 21 – “FEET”.