Question

PROBLEMIS CHAPTER Z Changes in Lengths of Axially Loaded Members 2.2 len ela anc 2.2-1 The L-shaped arm ABCD shown in the fige lies in a vertical plane and pivots about a horizontal pin at A. The arm has constant cross-sectional area and total weight W. A vertical spring of stiffness k supports the arm at point B. (a) Obtain a formula for the elongation of the spring due to the weight of the arm. (b) Repeat part (a) if the pin support at A is moved to D. rat elo ra di P al k le С В b 2 D DROR 2 21

Answer 1

Ret C be ~the cistance cj Centev a aavity of the bav trom A. WAB-0.BW Taring moment C werght Gbuvt boint A WAB Cb) Weo )2b = 0.8w(b)+o.2w (2b) o.Bw CbJ+0.2wl2b o.8bt .4b 2b Ca) Considerthe ree-boely diagam the bav SUmmingthe moment abo Ax point A Ay Jl2b - Fs Cb) wC1.2b) 0 Spring osce Fs 2W where ithe spring elongatton we KnoW

kさ= l.2 W oY .2 W Ang W xand Dy he reactwon ase Josces a point D. o. Sb CE2b Summin he momenks Gouur bo inr D : FS Cb)-W Co. 8b) 0 . Fs O.8 W Spng orce Fs ks O. W Spring etongaon: Ans 3 .: