A more elegant proof of the second uniqueness theorem uses Green's

identity (Prob. 1.61c), with T=U=V3. Supply the details.

Short Answer

Expert verified

Answer

It is proved as second uniqueness of theorem by using greens identity.

Step by step solution

01

Define function

Write the Greens identity.

~NT~N2U+~NU×~NT=T~NU×da…… (1)

Given that T=U=V3,

Therefore, the greens identity is changes as,

~NV3~N2V3+~NV3×~NV3=V3~NV3×da …… (2)

02

Determine proof of Greens identity

Since

2V3=2V1-2V22V1=-ρε02V2=-ρε0

Then,

2V3=-ρε0+ρε0=0

As known to us,

V3=E3

E3=V3as per derivation.

03

Determine proof of Greens identity

Substitute the above values in equation (1)

V30+E32dτ=-V3E3·daE32dτ=-V3E3·da …… (3)

As,

E3=E1-E2 …… (4)

If V is specified as V3=0or E3=0then,

The equation (4) will be,

0=E1-E2E1=E2

Thus, filed is uniquely determined.

And it is proved as this is a second uniqueness theorem.

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