To determine the coefficient of elasticity for steel and brass. This experiment did not directly measure any elasticity parameter, but only observed. E youngs modulus of elasticity pa e1 first youngs modulus of elasticity pa e2 second youngs modulus of elasticity pa e3 third youngs modulus of elasticity pa f force applied n g acceleration due to gravity 9. Pdf experimental work for mechanical properties of brick. Kinks should be removed from experimental wire before starting experiment. To determine youngs modulus of elasticity of the material of. A simple low cost demonstration experiment is performed using common apparatus in order to show various flexural patterns and to give a dynamical measure of young s modulus. Pdf laser lever method in the application of youngs. This is the working formula of the experiment, and is valid so long as the slope of the bar at any point with respect to the unstrained position is much less than unity. Im doing an experiment write up for the young modulus. This is an excellent follow up exercise to the youngs modulus experiment worksheet.
With the observation cycle completed per article 5. A simple experiment on flexural vibrations and youngs. Ying wang, rong shang, laser bending light lever to measure youngs modulus, physical experiment of college. Again with a uniform internal radial pressure q and free ends at r r, the hoop. Since the load w1 has been applied at the free end of the beam, the. This effect decreases with increasing aspect ratio. To calculate the youngs modulus of elasticity of the material of a bar by the method of flexure.
Youngs modulus experiment worksheet teaching resources. Youngs modulus past paper questions jan 2002 to jan 2009 note jan 2009 onwards is the new current exam specification. We used the concept of hookes law, which states that in a certain range, the strain or deformation of a material is proportional to the stress applied to it. When weight is added to wire, it experiences stress and strain. Although the examples in the textbook are about stretching material, the youngs modulus can also be found by compressing it. Niser an autonomous institute under dae, government of india. As the shown in figure 1 the sample was never taken past the elastic region. Bricks available in the market are taken for testing purpose. This is the working formula of the experiment, and is valid so long as the slope of the bar at any point with respect.
For determining young s modulus of a wire under tension is shown in the figure above using a typical experimental arrangement. Both the wires should be supported from same rigid support. Pdf young s modulus of solid material is usually measured by tensile test. Experimental techniques to determine the youngs modulus of. The hertzian model for elastic deformation specific to a point contact between a cylindrical object and the index finger has been used to curve fitting the experimental curve for elastic deformation of the finger in the vicinity of imposed forces from 0. To investigate the relationship between load, span, width, height and deflection of a beam, placed on two bearers and affected a concentrated load at the centre. Our aim is to determine the youngs modulus of elasticity of the material of a given wire using searles apparatus. Both the wires experimental and auxiliary should be of same length, material and crosssection. Nov 10, 2016 read this science lab report and over 89,000 other research documents. In practice, the estimated young s modulus from sonic logs is termed dynamic young s modulus. Students responded very positively to the experiment. Forces, elasticity, stress, strain and youngs modulus. In this lab you will measure the youngs modulus of a metal wire. They recommended using demonstrations and experiments throughout the semester as a way to reinforce the theory of strength of materials.
Perfect for alevel physics students on any specification. What i want to know is the problems that can occur during a standard classroom experiment that could effect the results and the calculation of the young modulus. To obtain the youngs modulus and shear modulus by the flexural vibration method, the shear deflection must be relatively large. Estimating youngs modulus from bond energies and structures. The theory before we move ahead, do you know what a searles apparatus is. Ratio of the linear stress to strain in this region is called youngs modulus. Youngs modulus means the ratio of longitudinal stress and longitudinal strain within elastic limit. Ying wang, rong shang, laser bending light lever to measure young s modulus, physical experiment of college. Experimental measurement of youngs modulus from a single.
Youngs modulus, numerical constant, named for the 18thcentury english physician and physicist thomas young, that describes the elastic properties of a solid undergoing tension or compression in only one direction, as in the case of a metal rod that after being stretched or compressed lengthwise returns to its original length. Pdf texture is an important attribute in the quality assessment of processed food products. Youngs modulus comprehensive materials testing system. In this experiment i am going to determine the youngs modulus e of wood from the period of oscillation of a loaded wooden ruler. First we consider solids, which include mostly nonbiological materials, such as metals, plastics, ceramics, and covalently bound solids like diamonds. Youngs modulus experiment youngs modulus experiment. In laying out the experiment the first step is to if vibrations are observed with a. The aim of this experiment is to measure the young modules of copper wire. It is an integral variable to consider when designing and engineering systems such as buildings or bridges.
Research a value for the young modulus of copper and comment on your result. The value for the young modulus i got was far off from the true value, but i think this was expected. L is the change in length of the material when the force is applied to it, l 0 is the initial length, and a is. Let us assume we have done an experiment where we have applied different. The proposed setup is suitable for a classroom experiment or a student training experiment. Similarly, the ordinary for youngs modulus as well as for shear modulus portland cement and sand which are usually and suggested the values for them. As experimental data are given in terms of yarn stiffness, the young modulus has to be updated during the simulation in order to ensure a constant stiffness of the yarn even when its crosssectional area changes, using the simple relation. Thathavebeentakencareofbyaddingsubtracting the error. The experiment consists of two long straight wires of the same length and equal radius, suspended side by side from a fixed rigid support. An undergraduate experiment on the vibration of a cantilever.
Several runs will be taken for the same sample to calculate the average value of young s modulus for the material. The young modulus cie as physics 201921 revision notes. Young s modulus, the young modulus or the modulus of elasticity in tension, is a mechanical property that measures the tensile stiffness of a solid material. This gives information about the elasticity of a material. This was our first lab, and the goal was to determine youngs modulus of elasticity of a thin wire by stretching. Background information what is youngs modulus, how do we use a stress strain curve to determine it, etc 3. Experimental determination of youngs modulus of elasticity. A rectangle copper plate of length x and width y is clamped snugly at two opposite corners, as shown in fig. Youngs modulus is a measure of the ability of a material to withstand changes in length under lengthwise tension or compression. The raw measurements are related but slightly different to make for a better experience in this evaluation worksheet. Youngs moduli are close enough to their actual values to determine that our apparatus to.
The temperature of the plate but not of the clamps is raised by. A more complete procedure can be done by taking into account the mass m of the vibrating length of the beam and thus the following equations are derived,b note. Jun 04, 1998 good agreement between experiment and theory is obtained. Youngs modulus for the cantilever material steel is determined from the observed frequencies of the fundamental mode for a series of different lengths, and the result is compared with that obtained from static deflection of the cantilever. Youngs modulus also referred to as the elastic modulus or tensile modulus, is a measure of mechanical properties of linear elastic solids like rods, wires, and such. Sonic young s modulus, non destructive materials testing. Determination of youngs modulus using the loaded cantilever. Experimental techniques to determine the youngs modulus of the. For solid wood and plywood, the youngs modulus shear modulus ratio ranges approximately from 5 to 20 hearmon 1948. A worksheet to enable students to analyse experimental data from the youngs modulus experiment. This is achieved in this report through constitutive equations that relate loads to deformations using the basic concepts of stress and strain. Modulus of elasticity the modulus of elasticity youngs modulus e is a material property, that describes its stiffness and is therefore one of the most important properties of solid materials. Apr 20, 2016 young s modulus is the measure of elasticity, equal to the ratio of stress acting on a substance to the strain produced.
Youngs modulus practical objective to determine the youngs modulus of a steel wire using a graphical method. In solid mechanics, youngs modulus is defines as the ratio of the longitudinal stress over longitudinal strain, in the range of elasticity the hooks law holds stress is directly proportional to strain. Youngs modulus past paper questions jan 2002 to jan 2009. It is difficult to evaluate youngs modulus and poissons ratio of thermal spray coatings because coatings are usually thin and attached to a thicker and much. Measurement of youngs modulus of anisotropic materials using. Future work for future work we wish to accomplish with the youngs modulus is to determine youngs modulus by testing variables with a standing wave setup. The youngs modulus of a material y is defined as the stress divided by the strain. It is the measure of elasticity and it is a very important characteristic of a material.
The wire is wrapped once around a cylindrical chuck. Measure the gradient of the straight portion of the graph and use this to calculate the young modulus for the copper. Youngs modulus,tensiontests, bending and compression. Questions prior to this are from the old spec and are the best fit we have note the change in style with the new specification. It quantifies the relationship between tensile stress force per unit area and axial strain proportional deformation in the linear elastic region of a material and is determined using the formula. Explain why a long wire is most suitable for this experiment. Modulus of elasticity definition, youngs modulus, formula. In this equation, f is equal to the force applied to the structure, y is the youngs modulus for the material. In this range, the shear deflection, which increases with increasing depthlength. Results of the youngs modulus by the pressure difference method71.
Youngs modulus and poissons ratio for thermal spray coatings are needed to evaluate properties and characteristics of thermal spray coatings such as residual stresses, fracture toughness, and fatigue crack growth rates. The initial longitudinal young modulus e 1 0 is determined directly using a tensile test on the fabric as shown in fig. Determination of youngs modulus by studying the flexural. Youngs modulus experiment evaluation worksheet teaching. Uniaxial tension and compression testing of materials.
This manual assumes the students know how to use all these instruments, he. Mechanical deformation puts energy into a material. When compared to the accepted value this represents a percent difference of 94. Youngs modulus y stressstrain youngs modulus can be used in the following equation. Although there is a clear difference in the apparent youngs moduli for the different orientations, a significant underestimation of youngs modulus was observed resulting from the substrate deformation as observed in both finite element simulation and experiment. Describe a good technique for measuring the diameter. Request pdf determination of young s modulus by studying the flexural vibrations of a bar. To calculate the youngs modulus,e of aluminium from measurement of the end deflection of cantilever beam of aluminium loaded at its free end to assess the accuracy and precision of this method by comparing the calculated value of e to the known value eal72. Youngs modulus is a numerical constant, named after the 18thcentury english physician and physicist thomas young. A cantilever beam method for evaluating youngs modulus and. Searles apparatus consists of two metal frames f1 and f2.
A static modulus is directly measured in a deformational experiment. First to determine the youngs modulus of wood, we used a wooden cantilever loaded. Abstract youngs modulus is a measure of deformation of a material in response to an applied force. Pdf youngs modulus of solid material is usually measured by tensile test. Pdf a simple experiment on flexural vibrations and youngs. Conclusions measuring youngs modulus with a centrallyloaded beam requires less equipment than the. There are other numbers that give us a measure of elastic properties of a material, like bulk modulus and shear modulus, but the value of youngs modulus is most commonly used. The young modulus is defined as the ratio of stress and strain. On the other hand, the elastic modulus shows relatively less sensitivity to specimen size. Youngs modulus is named after thomas young,19th century,british scientist. The young modulus is the measure of the ability of a material to withstand changes in length with an added load ie. The data collected in the video can be used to complete a table and graph. Introduction the main purpose of this article is to suggest a very low cost setup for an experiment on.
Analysis of the data obtained from the experiment to determine the young s modulus of a metal wire using a travelling microscope. Youngs modulus is also termed the modulus of elasticity. Youngs modulus of a metre ruler 1076 words bartleby. For 20 gauge copper wire the following experimental results produced a young s modulus constant of 6063 mpa, or 6. Manual hand operation may distort the structure while. Niser an autonomous institute under dae, government of. Experimental measurement of youngs modulus from a single crystalline cementite bonwoong koo,a,1 young jin chang,a,1 seung pyo hong,a chan soon kang,b shin woong jeong,c wonjong nam,c iljeong park,d young kook lee,d kyu hwan ohb and young woon kima. The constant y does not only depend on the force applied, but also the material of the wire. Stress is the tension or compression force per unit area fa. Static moduli are often used in insitu stress analysis and wellbore stability application to evaluate pore pressure, possible breakouts, and tectonic stress distribution.
Youngs modulus is a measure of the ability of a material to. Therefore, one can say that size is less important for testing this tuff with respect to elastic modulus. Youngs modulus is used practically in a variety of settings, but one interesting application is the need for engineers. Explain the experiment to determine youngs modulus of the. Pdf measuring youngs modulus the easy way, and tracing the. Nov 25, 2016 the same value can be used to get a single average value of youngs modulus y. The intact core sample was selected without fissure and crack in it. Youngs modulus measurement of thin films by resonant. Youngs modulus is being combined with other topics to create a more applied style of question. The circuit for the experiment with the wheatstone bridge. To determine youngs modulus of elasticity of the material. Introduction youngs modulus is a material property that is very useful. Exam tip although every care should be taken to make the experiment as reliable as possible, you will be expected to suggest improvements in producing more accurate and reliable results e. Youngs modulus is a material property that is very useful.
Youngs modulus can therefore be calculated once the. If at the lower end of wire of length l and crosssectional area of a a load of m is pressed and if the length increases by l, then. By using an optical lever, the change in length can be measured. Calculate the value of young s modulus of aluminumbar by nonuniform bending. The youngs modulus can only be derived experimentally, there are no theoretical methods by which the youngs modulus of a material can be calculated therefore in this experiment our aims were. In the process, you will gain an understanding of the concepts of stress and strain. The values of youngs modulus for elasticity e for 0. The machine used in this experiment was an electronic. Pdf sonic youngs modulus, non destructive materials. Determine the value of young s modulus of given steel bar having breadth 3cm and thickness 0. Experimental and theoretical approaches an experimental. A nodal point is recognized at a distance of about 0.
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