Practical part. 1.To plug a device in a network 220 V and to press the switch of „СЕТЬ '”

1.To plug a device in a network 220 V and to press the switch of „СЕТЬ '”.

2. To press the switch of “СБРОС”. Carefully to turn a scope to its fixing due to reaching of small flag by a 7 electromagnet 6.

3. To press a switch „ПУСК”. An electromagnet will release a scope, and it will begin to carry out turning oscillations. An electronic block will deduct the amount of full oscillations and time of oscillations.

4. When a number 9 will appear on the indicator of amount of oscillations, to press a switch “СТОП”. Upon termination of 10th oscillation stop-watch of stop.

5. To define the period of oscillations, dividing time into the amount of oscillations, that on 10.

6. To push back a switch “ПУСК”. To execute measuring of period of oscillations of T_r in obedience to points 2 ÷ 5 three times. To add results to the table 14.1.

Table 14.1

№	T, s	ΔT, s	(ΔT)2, s2
	=		∑(Δ Т рі)2=

Measure a Vernier calipers the diameters of cylinder (length of peg) and ball. Carefully, not to cut a wire short, fasten a load in a scope. For this purpose to release nuts 11, to move a slat 10 up, how downward, that centrings dowels 14.

7. Got in openings on a load. To twirl nuts and clutch a load spirally 12. To fasten a cylinder along his axis, peg - athwart to the plane of scope.

8. Like points 2 ÷ 5 to measure the period of oscillations on once for all loads, including for a ball. To add the results of measurings to the table 14.2.

Table 14.2.

№	R (L), mm	Т, s	Т 2, s2	R 2 (L 2), mm2
Ball

9. To build the chart of dependence of T² = f(R²), or T² = f(L²). To continue a chart to crossing with the axis of ordinates and on a segment which is chopped off on it, to define the square of period of oscillations of free scope .

10. On lineal part of graphic (fig.14.2) a little rather one from the second to choose two points 1 and 2. To define their co-ordinates for to the axes, but not from a table. To find the tangent of corner φ to inclination of graphic by formula

, (14.20)

or . (14.21)

11. After formulas (14.17), (14.20) for cylinders, or (14.18), (14.21) for pegs to calculate a numerical value

. (14.22)

12. Putting the got value, and also mean value , from a table 1 in a formula (14.19), calculate the square of period of oscillations of ball and compare it to directly measured (see a table 14.2).

13. To define the value of ordinate which is chopped off by the graphic T² = f(R²). To compare this value to the square of period of oscillations of scope.

14. Draw conclusion that to implementation of laws of oscillations of the turning pendulum, and also about justice of formulas for the moments of inertia of cylinder, peg, ball.

Figure 14.3