Лабораторные работы / Решенная лабораторная по физике 28
.docThe laboratory work No 28.
Definition of a toroid’s inductance with a ferromagnetic core.
Had done by the student gr.__220171я__ F.N.S. Pavlov F.E.
Checked by ______________________ date ____________
Purpose: study the dependence of toroid’s inductance on a current value.
The order of performing a work:
F
ig.1
The principle scheme of the laboratory work.
While
the current flowing along the wire, the magnetic field E0
is formed (outside it), and inside
approximately equal.
, (1)
where H – strength inside the toroid; N – entire number of loops; n – number of loops per unit of toroid length.
(2)
where B – magnetic field
induction;
- magnetic constant;
- relative magnetic permeability
of the medium.
Magnetic
induction vector
flow: 
.
- flow
through one toroid loop
(3)
(4)
where L – induction.
(5)
For
non-ferromagnetic wires
,
(6)
where U – effective voltage;
- magnetic resistance;
- capacity resistance;
- circuit (cycle) frequency.
, 
, where
, 
Henry.
Table 1.
-
№
I, 10-3 A
U, V
L, Henry
1
5
18
104.667
2
10
42
108.276
3
15
60
119.241
4
20
65
128.163
5
25
79
130.833
6
30
82
132.676
7
35
83
112.143
8
40
84
96.615
9
50
86
61.435
10
60
87
49.632
Conclusion:
So we have studied the dependence of toroid’s inductance on a current value.