Group 4
مرحبا بك في منتدى قروب 4 نحن سعيدون بتواجدك معنا سوف تجد لدينا كل المحاضرات والبرامج والفيديوهات نرجوا ان تتفضل بالتسجيل معنا لتنال كافة الصلاحيات في المنتدى
welcom to group 4 we happy to see you here plzz join to us Smile

Group 4

المحاضرات بالاسفل .... اذا اردت اي محاضرة او اي طلب اكتبه في غرفة الطلبات وسيتم الاستجابه في اقرب وقت وشكرا ....
 
الرئيسيةاليوميةس .و .جبحـثالأعضاءالمجموعاتالتسجيلدخول
بحـث
 
 

نتائج البحث
 
Rechercher بحث متقدم
سحابة الكلمات الدلالية
المواضيع الأخيرة
» Integration by Parts
الأحد مارس 31, 2013 7:16 pm من طرف Admin

» Integration by parts -
الأحد مارس 31, 2013 7:12 pm من طرف Admin

» Biot-Savart Law
الأربعاء مارس 27, 2013 6:21 pm من طرف Admin

» Law of Biot-Savart
الأربعاء مارس 27, 2013 6:18 pm من طرف Admin

»  the biot - savart law
الأربعاء مارس 27, 2013 6:17 pm من طرف Admin

» Integration by substitution
السبت مارس 23, 2013 4:44 pm من طرف Admin

» Integration by Substitution : tutorial 1 : ExamSolutions
السبت مارس 23, 2013 4:43 pm من طرف Admin

» Integration using U-Substitution
السبت مارس 23, 2013 4:41 pm من طرف Admin

» Integration by Substitution
السبت مارس 23, 2013 4:40 pm من طرف Admin

أبريل 2018
الإثنينالثلاثاءالأربعاءالخميسالجمعةالسبتالأحد
      1
2345678
9101112131415
16171819202122
23242526272829
30      
اليوميةاليومية
تسجل الدخول
  • تذكرني؟
  • التبادل الاعلاني

    انشاء منتدى مجاني




    شاطر | 
     

      the biot - savart law

    اذهب الى الأسفل 
    كاتب الموضوعرسالة
    Admin
    Admin
    avatar

    عدد المساهمات : 116
    نقاط : 19951
    السٌّمعَة : 1
    تاريخ التسجيل : 08/03/2013
    العمر : 23

    مُساهمةموضوع: the biot - savart law   الأربعاء مارس 27, 2013 6:17 pm

    The Biot-Savart law

    According to Eq. (316), we can obtain an expression for the electric field generated by stationary charges by taking minus the gradient of Eq. (335). This yields
    (336)

    which we recognize as Coulomb's law written for a continuous charge distribution. According to Eq. (318), we can obtain an equivalent expression for the magnetic field generated by steady currents by taking the curl of Eq. (334). This gives
    (337)

    where use has been made of the vector identity . Equation (337) is known as the Biot-Savart law after the French physicists Jean Baptiste Biot and Felix Savart: it completely specifies the magnetic field generated by a steady (but otherwise quite general) distributed current.
    Let us reduce our distributed current to an idealized zero thickness wire. We can do this by writing
    (338)

    where is the vector current (i.e., its direction and magnitude specify the direction and magnitude of the current) and is an element of length along the wire. Equations (337) and (338) can be combined to give
    (339)

    which is the form in which the Biot-Savart law is most usually written. This law is to magnetostatics (i.e., the study of magnetic fields generated by steady currents) what Coulomb's law is to electrostatics (i.e., the study of electric fields generated by stationary charges). Furthermore, it can be experimentally verified given a set of currents, a compass, a test wire, and a great deal of skill and patience. This justifies our earlier assumption that the field equations (277) and (278) are valid for general current distributions (recall that we derived them by studying the fields generated by infinite, straight wires). Note that both Coulomb's law and the Biot-Savart law are gauge independent: i.e., they do not depend on the particular choice of gauge.

    Figure 33:

    Consider an infinite straight wire, directed along the -axis, and carrying a current (see Fig. 33). Let us reconstruct the magnetic field generated by the wire at point using the Biot-Savart law. Suppose that the perpendicular distance to the wire is . It is easily seen that
    (340)
    (341)
    (342)
    (343)

    Thus, according to Eq. (339), we have

    (344)

    which gives the familiar result
    (345)

    So, we have come full circle in our investigation of magnetic fields. Note that the simple result (345) can only be obtained from the Biot-Savart law after some non-trivial algebra. Examination of more complicated current distributions using this law invariably leads to lengthy, involved, and extremely unpleasant calculations.
    الرجوع الى أعلى الصفحة اذهب الى الأسفل
    معاينة صفحة البيانات الشخصي للعضو http://group4.allgoo.net
     
    the biot - savart law
    الرجوع الى أعلى الصفحة 
    صفحة 1 من اصل 1

    صلاحيات هذا المنتدى:لاتستطيع الرد على المواضيع في هذا المنتدى
    Group 4 :: المحاضرات الهامه :: محاضرات الفيزياء-
    انتقل الى: