Mathematical questions with their solutions, from the "Educational times" Volume 23
D. Biddle
Paperback
(RareBooksClub.com, May 22, 2012)
This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1884 Excerpt: ...to tho direction of its movement. Solution by the Proposer. Taking for axes of coordinates any pair of rectangular diameters of the plate in its original position, and denoting by r its radius, by I and m the components of its small movement of translation, by and T1 those of the resulting small displacement of any point xy of the lamina, and by « and v the potential and displacement functions respectively of the strain; then since, by hypothesis, = 0 and ij = 0 for all positions of xy at infinity, while for all points on the circumference of the plate in its original position, that is, for all points satisfying the equation x-+ y" = r', they arc connected with x and y hy the relation (x + £--l)2 + (y + 17--mf = r., or, neglecting small quantities of the second order, by the relation xg+yq = lx + my; we have accordingly, for the solution of the entire problem (including the above particulars) of the strain, first to find, if possible, a potential function u which shall satisfy, at once, the general equation 1 = 0 throughout the entire extent of the lamina, and the dx. dy aforesaid particular conditions at its outer and inner boundaries, and Ihen derive from it the corresponding displacement function v in tho usual manner. Both functions, in the present case, are found readily as follows. As the function Ix t my is homogeneous in x and y, and satisfies for all values of them the equation---+----= 0, therefore the function dx dy' k.----, where k is any constant, satisfies, for all values of k, the x +9" J.; 2 A general equation--+--= 0 throughout the entire extent of the lamina, dx: dyand the particular conditions = 0 and i)--0 at its outer boundary, and for the particular value k = r'-that for its inner boundary also. It follows therefore...