SOLUTION : 



(a) Equation 2-3, 



Equation 2-1, 



2ir \ L , 



T 



Therefore, equating 2-1 and 2-3, 



T 2n \ L r 



and multiplying both sides by (2tt)2/lt 



Hence, 



(2i:y L _ (2nr gT , /27:d^ 

 LT T = IF ^ '^"MX; 



i2ny 27rg ^ Ayrd^ 



(bj Equation 2-13 may be written 



^ ^ gTH cosh[27r(z+d)/L] /2nx _ 27Tt\ 



2L cosh (27rd/L) """M L ~ T J 



^ 1 gH cosh[27r(z + d)/L] hnx 27rt^ 



C 2 cosh(27rd/L) ^""llT ~ F; 



since 



T _ 1 

 L ~ C 



Since 



C = C .anh M 

 2n \ L J 



^ ^ ^ 1_ cosh[27r(z + d)/L] /27rx _ 2n^ 



T tanh(27rd/L) cosh (27rd/L) ^°' I L ~T"y 



2-19 



