1. בהתבסס על האיור למטה, אם רדיוס העקמומיות של החוט הוא 50 ס"מ, קבע את גודל ה- השדה המגנטי במרכז העקמומיות (בנקודה 0, ראה איור למטה). (µo = 4π.10-7 Wb.A-1 m-1)
ידוע:
רדיוס (r) = 50 ס"מ = 0.5 מטר
זרם חשמלי (I) = 1.5 אמפר
חדירות הוואקום (µo) = 4π.10-7 Wb.A-1 m-1
מבוקש: Tגודל השדה המגנטי
פתרון:
360o = 1 הֶקֵף of a circle. 120o / 360o = 1/3 then 120o = 1/3 x הֶקֵף of a circle.
The equation of the magnetic field at the center of the coil with several loops :
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B = the magnitude of the magnetic field, N = number of loops, I = electric current, r = radius of curvature
In the above problem, there is only one loop so that N is eliminated from the equation. The wire coil on the above problem is not 1 circle but 1/3 circle :
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The magnitude of the magnetic field at the center of curvature :

2. Based on the figure below, the electric current flows in the wire is 6-A and radius of curvature is R = 3π cm, to determine the magnitude of the magnetic field at point P.
ידוע:
Radius of curvature (r) = 3π cm = (3π/100) m
= 3π/102 m = 3π.10-2 m
זרם חשמלי (I) = 6 אמפר
חדירות הוואקום (µo) = 4π.10-7 Wb.A-1 m-1
מבוקש: The magnitude of the magnetic field
פתרון:
360o = 1 הֶקֵף of a circle. 45o / 360o = 1/8 then 45o = 1 / 8 x הֶקֵף of a circle.
The magnitude of the magnetic field at the center of curvature :

3. Electric current flows in wire = 9-A, the radius of curvature (R) = 2π cm and µo = 4π.10-7 Wb.A-1.m-1, determine the magnitude of the magnetic field at point P.
ידוע:
Radius of curvature (r) = 2π cm = (2π/100) m
= 2π/102 m = 2π.10-2 m
זרם חשמלי (I) = 9 אמפר
חדירות הוואקום (µo) = 4π.10-7 Wb.A-1 m-1
מבוקש: The magnitude of the magnetic field at point P
פתרון:
360o - 120o = 240o. 240o / 360o = 2/3 then 240o = 2/3 x הֶקֵף of a circle.
The magnitude of the magnetic field at the center of curvature :
