RF/Microwave Engineering and Applications in Energy Systems. Abdullah Eroglu
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СКАЧАТЬ circ semicolon equals ModifyingAbove phi With ampersand c period circ semicolon"/>

      In a spherical coordinate system, unit vectors are defined as

      (1.9)

      which leads to

      (1.10b)

      (1.10b)

      (1.10c)

      1.2.1.2 Vector Operations and Properties

       Dot Product

and
shown in Figure 1.2a. The dot product of these two vectors are then expressed as

      (1.11)

      If θ between two vectors is 90°, then the dot product of these two vectors is equal to zero.

and
for dot product. (b) Representation of vectors ModifyingAbove upper A With right-arrow and ModifyingAbove upper B With right-arrow for cross product.

Schematic illustration of unit vector representation in a Cartesian coordinate system.

       Cross Product

      The cross product between two vectors is also a vector. The magnitude of the cross product of ModifyingAbove upper A With right-arrow and ModifyingAbove upper B With right-arrow is equal to the area of the parallelogram which is formed by these vectors, as shown in Figure 1.2b. Consider the two vectors given in Figure 1.2b. The cross product of these two vectors can be written as

      (1.12)upper A times upper B equals bar upper A StartAbsoluteValue EndAbsoluteValue upper B bar sine theta ModifyingAbove a With ampersand c period circ semicolon Subscript n

      ModifyingAbove a With ampersand c period circ semicolon Subscript n is the unit vector along the normal to the plane containing A and B. It is important to note that

      (1.13)ModifyingAbove upper A With right-arrow times ModifyingAbove upper B With right-arrow equals minus ModifyingAbove upper B With right-arrow times ModifyingAbove upper A With right-arrow

       Vector Operation Properties for Dot and Cross Products

      Some of the properties for dot and cross products are given below

      (1.14a)Commutative right-arrow ModifyingAbove upper A With right-arrow dot ModifyingAbove upper B With right-arrow equals ModifyingAbove upper B With right-arrow dot ModifyingAbove upper A With right-arrow

      (1.14b)Commutative right-arrow ModifyingAbove upper A With right-arrow times ModifyingAbove upper B With right-arrow equals minus ModifyingAbove upper B With right-arrow times ModifyingAbove upper A With right-arrow

      (1.15a)Distributive right-arrow ModifyingAbove upper A With right-arrow dot left-parenthesis ModifyingAbove upper B With right-arrow plus ModifyingAbove upper C With right-arrow right-parenthesis equals ModifyingAbove upper A With right-arrow dot ModifyingAbove upper B With right-arrow plus ModifyingAbove upper A With right-arrow dot ModifyingAbove upper C With right-arrow

      (1.15b)Distributive right-arrow ModifyingAbove upper A With right-arrow times left-parenthesis ModifyingAbove upper B With right-arrow plus ModifyingAbove upper C With right-arrow right-parenthesis equals ModifyingAbove upper A With right-arrow times ModifyingAbove upper B With right-arrow plus ModifyingAbove upper A With right-arrow times ModifyingAbove upper C With right-arrow

      (1.16a)СКАЧАТЬ