Лабораторные работы / Решенная лабораторная по физике 22

The laboratory work N^o 22.

Measuring a resistance of the conductors.

Had done by the student gr.__220171я__ F.N.S. Pavlov F.E.

Checked by ______________________ date ____________

Purpose:

Defining a resistance of the galvanometer using Thomson’s bridge.

The order of performing a work:

The current flow from the conductor is satisfies By the Ohm’s low: (1).

The resistance of the cylindrical conductor is (2).

The density of the current is (3).

The Ohm’s low in the local form is (5).

If we create an electrical field in the conductor , the electrons will start a ranked moving with the average driftage velocity v_d . At which (6). So we may assume that (7).

From the (7) to (6) we have (9) and (10).

Table N^o1.

No	U, V	I, 10-3A	l, m	S, m2	, ohm*m	<>, ohm*m	, ohm*m	<>, ohm*m	E, %
1	1.00	270	0.35	0.28
2	0.80	270	0.25
3	0.45	270	0.15

Table N^o2.

No	R0, Ohm	l, m	Rx, ohm	<Rx>, ohm	Rx, ohm	<Rx>, ohm	E, %
1	1000	28.4
2	4700	23.0
3	1000	29.0
4	4700	23.8
5	1000	29.8
6	4700	24.1

Conclusion:

So we have define a resistance of the galvanometer using Thomson’s bridge.

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