The discussion revolves around understanding the factors affecting beam deflection in double cantilever beams that are fixed at both ends. The original poster seeks clarification on how length, width, and thickness influence deflection without delving into the formulas involved.
The conversation includes attempts to clarify the original poster's question and to provide insights into the underlying physics. Some participants suggest that the moment of inertia is a more relevant factor than area in this context, indicating a productive exploration of concepts.
Participants note that the original poster is looking for a conceptual understanding rather than a mathematical explanation, which shapes the nature of the responses and discussions.
Tammy, I'm not sure what you mean by the 'physics' part of it; for a given load and end conditions, the deflection of any beam will increase when its length increases or when its width or depth (its area moment of inertia) decreases, per the deflection formula which is a function of load, boundary conditions, material elasticity, and the geometric properties of the beam. Are you looking for the math behind the physics? If this is a homework question, can you be a bit more specific and show some attempt at answering your own question?Tammy... said:Homework Statement
Can someone please tell me why in a double cantilever beam (fixed at both ends) the deflection increases when the length increases, the defelction decreases when the width increases and the deflection decreases when the thickness increases. I don't want to no why it does these in relation to the formula... just the physics part of it... thanx
That's pretty much correct, except, to be technically correct, you should substitute the word "area (A)'' with the term "moment of inertia (I)". In beams subjected to bending loads, both stress and deflection are functions of I, not A, although I and A are related.Tammy... said:Um... well its for an assignment... does the deflection decrease when the thickness and width increase becasue there is more area... like there is less stress because it is spread over a larger area which would cause less deflection?