The cooperative effects of tension and elasticity
Definition of elasticity and elastic force, and examples of the use of elastic force. Learn about elasticity and how to determine the force exerted by a spring. Hooke's law tells us that there is a linear relationship between force and extension. Problem: What is the relationship between the force applied to a spring and the An elastic body has the ability to regain its original form after it is stretched. of the spring by pulling slowly on the spring and observe the tension in the spring.
The value of E depends on the material; the ratio of its values for steel and rubber is aboutIt expresses, in terms of macroscopic quantities, something about the nature or constitution of the material. This theory is commonly applied in the analysis of engineering structures and of seismic disturbances.
What is Hooke's Law?
The elastic limit nearly coincides with the proportional limit for some elastic materials, so that at times the two are not distinguished; whereas for other materials a region of nonproportional elasticity exists between the two. The linear theory of elasticity is not adequate for the description of the large deformations that can occur in rubber or in soft human tissue such as skin.
It is available for transfer into other forms of energy—for example, into the kinetic energy of a projectile from a catapult. In this way, the elastic response of any solid in tension can be characterized by means of a stored-energy function.
An important aspect of the theory of elasticity is the construction of specific forms of strain-energy function from the results of experiments involving three-dimensional deformations, generalizing the one-dimensional situation described above. Strain-energy functions can be used to predict the behaviour of the material in circumstances in which a direct experimental test is impractical.
In particular, they can be used in the design of components in engineering structures. For example, rubber is used in bridge bearings and engine mountings, where its elastic properties are important for the absorption of vibrations. Steel beams, plates, and shells are used in many structures; their elastic flexibility contributes to the support of large stresses without material damage or failure. The elasticity of skin is an important factor in the successful practice of skin grafting.
Within the mathematical framework of the theory of elasticity, problems related to such applications are solved. The results predicted by the mathematics depend critically on the material properties incorporated in the strain-energy function, and a wide range of interesting phenomena can be modeled.
But I'm not sure 3D assembly in this kind of a soft gel has been done.Relation between Youngs Modulus, Coefficient Of Linear Expansion, thermal stress #elasticity #force
It's new," she said. A non-magnetic attraction Chakrabarti made videos of her experiments using a CCD charge-coupled device camera equipped with a microscope. The particles look like two magnets attracted to each other, but no magnetic force is involved.
Before Chakrabarti drops a sphere onto the surface of the gel, the surface is straight.
Each time she drops a sphere, it plunges into the gel, deforming the gel surface. The gel folds and closes around the top of the sphere due to hoop stress and surface tension, leaving a thin channel from the sphere to the surface. It's as if the gel stitches itself up again around the sphere, Chakrabarti says. The sphere's effective weight is balanced by the deformed elastic field inside the gel.
When she drops another sphere some distance away, the same thing happens. As the gel is being deformed in two places, tensile stress fields form in the gel parallel to the surface.
Nothing counterbalances this stress field, so the gel between the two spheres is squeezed out of the way, allowing the two spheres to approach each other and finally touch.
Elasticity | physics | dayline.info
The same interaction occurs between two multi-sphere structures in the gel. Chakrabarti found that the attraction is due to the difference between the potential energy released as the sphere descends and a subsequent increase in the elastic energy. The attraction between two spheres depends on the relationship between the depth to which they are submerged and the separation between them.
She used an image analysis software called ImageJ to measure the change in depth of the particles and the distance between two particles as they move towards each other.
Forces and elasticity - AQA
The experiments, said Chaudhury, represent "the discovery of an effective force that hasn't been seen before, by combining all of these known components: Such a model is the scientific starting point for further research that could one day be used for 3D crystallization of structures at the mesoscale. A concrete application is still probably years away, Chaudhury says.
But Chakrabarti has made a new scientific discovery, one that will fuel future research by other scientists and engineers.
The two researchers hope to explore possible applications of Chakrabarti's phenomenon in the fields of soft actuators and self-assembly processes. Their goal is to accomplish this by combining the properties of a gel with those of liquid crystal, whose elastic fields are self-induced by the interactions of the particles in the surrounding medium.
So far, no rigorous theory has been developed to account for the phenomenon that requires solutions of nonlinear field equations. However, Chakrabarti and Chaudhury have been able to develop a model at a scaling level that captures the main physics underlying the phenomenon. Chakrabarti anticipates completing her Ph.
- The cooperative effects of tension and elasticity
She also published a Langmuir paper with Chaudhury in May that describes their analysis of elastocapillarity in adhesion-induced instability in thin films and the surface tension of the soft elastic hydrogel that she used in her later experiments.