I Question about elasticity to help my understanding

  • I
  • Thread starter Thread starter samy4408
  • Start date Start date
  • Tags Tags
    Elasticity
AI Thread Summary
Elasticity is defined as the change in pressure over the change in volume (∆p/∆v), which can be confusing when considering everyday materials like wood. Wood is not considered very elastic because it does not significantly change volume under pressure, and its behavior is better described by compressibility. Linear isotropic elasticity requires two constants, including the bulk modulus K, and while literature may present more constants, any two can uniquely explain elasticity. Elastic materials return to their original shape after forces are removed, but excessive force can lead to inelastic behavior. Wood's heterogeneous and anisotropic nature limits the applicability of linear isotropic elasticity, necessitating the use of more general elasticity forms in certain situations.
samy4408
Messages
62
Reaction score
9
Hello, today we learned about elasticity, whose formula was the change of pressure over the volume change (∆p/∆v), which seemed very weird compared to the use of the adjective elastic daily, my question is can we say that a piece of wood is very elastic? because even applying a large pressure will not change the volume that much.
hoping for a replay, and thanks.
 
Physics news on Phys.org
I agree it seems very odd. The reciprocal of elasticity is compressibility, which seems to suit the purpose better.
 
What is the full formula?
Linear isotropic elasticity requires two physical constants. One of them, the bulk modulus K, is explained with ΔP/ΔV. In the literature, you will find more than 2 constants, but any two of them can be used to explain things uniquely. There are formulas to convert between them.
An elastic material returns to its original size and shape when applied forces are removed. Large enough forces can cause inelastic behavior.
Wood is heterogenous and anisotropic, so linear isotropic elasticity can only be used in certain situations. There are more general forms of elasticity that can be used for more general cases.
 
Last edited:
Consider an extremely long and perfectly calibrated scale. A car with a mass of 1000 kg is placed on it, and the scale registers this weight accurately. Now, suppose the car begins to move, reaching very high speeds. Neglecting air resistance and rolling friction, if the car attains, for example, a velocity of 500 km/h, will the scale still indicate a weight corresponding to 1000 kg, or will the measured value decrease as a result of the motion? In a second scenario, imagine a person with a...
Thread 'Gauss' law seems to imply instantaneous electric field propagation'
Imagine a charged sphere at the origin connected through an open switch to a vertical grounded wire. We wish to find an expression for the horizontal component of the electric field at a distance ##\mathbf{r}## from the sphere as it discharges. By using the Lorenz gauge condition: $$\nabla \cdot \mathbf{A} + \frac{1}{c^2}\frac{\partial \phi}{\partial t}=0\tag{1}$$ we find the following retarded solutions to the Maxwell equations If we assume that...
Dear all, in an encounter of an infamous claim by Gerlich and Tscheuschner that the Greenhouse effect is inconsistent with the 2nd law of thermodynamics I came to a simple thought experiment which I wanted to share with you to check my understanding and brush up my knowledge. The thought experiment I tried to calculate through is as follows. I have a sphere (1) with radius ##r##, acting like a black body at a temperature of exactly ##T_1 = 500 K##. With Stefan-Boltzmann you can calculate...
Back
Top