Example of the Method of Reduction
Example (cont)
The general solution from the method of reduction is: y(r) = C1r + C2/r
Recall that the inner cylinder has radius, a, and the outer cylinder has radius, b. Apply
the boundary conditions.
y(a) = a ω and y(b) = 0
C1b + C2/b = 0 and C1 a + C2/a = a ω
The solution for C1 and C2 is:
C1 = - a2 ω/ [ b2 - a2 ]
C2 = a2 b2 ω/ [ b2 - a2 ]
y(r) = - a2 ω r / [b2 - a2 ] + a2 (b2/r)ω / [b2 - a2 ]
y(r) = a2 ω [ b2/r - r) / [ b2 - a2 ] (result)
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