For this reason wavelength is often expressed using the unit nanometer, where 1 meter is equivalent to 109 nanometers. c. The fourth nodal line on an interference pattern is 8.4 cm from the first antinodal line when the screen is placed 235 cm from the slits. Although Young's modulus is named after the 19th-century British scientist Thomas Young, the concept was developed in 1727 by Leonhard Euler. To illustrate some typical results from this experiment and the subsequent analysis, consider the sample data provided below for d, y, L and m. (Note: AN0 = central antinode and AN4 = fourth antinode). An interference pattern is produced when light is incident upon two slits that are 50.0 micrometers apart. Academic year. The Young’s modulus, one of the elastic constants, is dened as the ratio of stress to strain Y = F A l l A)area l)length of the non-extended rectangular block Thus, for a rectangular block, Young’s modulus has the form Y = Fl A l (2) 2 ��C����"�ð�u������|-FKXNJ2�d]��iUO����U�� e�o�q��s�SYn���'xr�jn�#/��5p��l���Z���o7O�e�\� And since there are 100 centimeters in 1 meter, the 10.2 cm is equivalent to 0.102 m. Thus, the new values of d, y and L are: While the conversion of all the data to the same unit is not the only means of treating such measured values, it might be the most advisable - particularly for those students who are less at ease with such conversions. As discussed in the previous part of this lesson, it was important that the two sources of light that form the pattern be coherent. (GIVEN: 1 meter = 109 nanometers). stream The converted values are listed in the table above. The Theory Before we move ahead, do you know what a Searle’s apparatus is? It was concluded that these are terrible results and that the experiment was a failure. Also note that the given values have been converted to cm.). 4 0 obj Each frame has a torsion head at the upper side and a hook at the lower side. (Note that m = 6 corresponds to six spacings. The stated distance is twice as far so the m value must be doubled. Poisons ratio (σ) 3. Thus, m = 6.5. Young's modulus describes tensile elasticity along a line when opposing forces are applied. The reference wire and test wire are hung from the ceiling. (Note that m = 4.5 represents the fifth nodal position or dark band from the central bright band. good and superb. If there are 109 nm in 1 meter, then there must be 107 nm in the smaller centimeter. They are Pin and Microscope method and Optic lever method. 2015/2016. Set up clamps, pulleys and wires as shown in the diagram. Rather than using a note card to split the single beam into two coherent beams, a carbon-coated glass slide with two closely spaced etched slits is used. could not serve as coherent light sources. Also note that the given values have been converted to cm. dr r (1) Here, dM=1 gm, dT=0.01s, dR=0.01mm, dr=0.01mm Also, M=2062 gm, T=0.94s, R=6.89mm, r=0.72mm Plugging the values in (1), we get, dη η = 0.054 (2) So, percentage error =dη η ×100 = 5.40% Hence, corrected reading = (94 ± 5) × 109N/m2 5 The slits are separated by 25.0 micrometers. This is not recommended and can be addressed through good experimental practice and careful measurement. Young Modulus - Physics A-level Required Practical - YouTube To obtain two sources of light, Young used a small paper card to break the single pinhole beam into two beams, with part of the beam passing by the left side of the card and part of the beam passing by the right side of the card. The slotted masses can be used to vary the force acting on the test wire. The force on the test wire can be varied using the slotted masses. endstream Also note that the given values have been converted to cm. Users may need to adapt the risk assessment information to local circumstances. Multimedia University. Multiplying by 109 will convert the wavelength from meters to nanometers (abbreviated nm). The Young Modulus for a wire can be measured using this equipment. Also note that the given values have been converted to cm. Aim of this experiment is to find the Young's modulus of the given material by uniform bending using pin and microscope method. Trajectory - Horizontally Launched Projectiles Questions, Vectors - Motion and Forces in Two Dimensions, Circular, Satellite, and Rotational Motion, Anatomy of a Two-Point Source Interference Pattern, Other Applications of Two-Point Source Interference, Lesson 3 - Mathematics of Two-Point Source Interference. The diagram below depicts the results of Young's Experiment. e. Two slits that are 0.200 mm apart produce an interference pattern on a screen such that the central maximum and the 10th bright band are distanced by an amount equal to one-tenth the distance from the slits to the screen. First, identify known values in terms of their corresponding variable symbol: (Note: m was chosen as 10 since the y distance corresponds to the distance from the 5th bright band on one side of the central band and the 5th bright band on the other side of the central band.). Both static and dynamic modulus methods are covered in this Guide, presented in separate sections with details on the different test methods and on practical issues affecting the quality and accuracy of the measurement. ( Note that there are three spacings between the second and the fifth bright bands. Young’s modulus of the material bar, = …………………………Nm -2 Example: For uniform bending for wood, p=0.5m, m= 0.02kg, g=9.8ms -2, pl 2 /e = 2.165 m 2, b=2.956 x 10 -2 m,d=50693 x 10 … x� The slide with its slits is most commonly purchased from a manufacturer who provides a measured value for the slit separation distance - the d value in Young's equation. Export citation and abstract BibTeX RIS. b. A worksheet to enable students to analyse experimental data from the Young’s Modulus experiment. The fifth and the second antinodal line on the same side of the pattern are separated by 98 mm. ( Note that the fourth nodal line is assigned the order value of 3.5. To find the Young's modulus of the given material bar by non uniform bending using pin and microscope method. >> The bulk modulus (K) is like Young's modulus, except in three dimensions. <> The perpendicular distance from the midpoint between the slits to the screen is 7.65 m. The distance between the two third-order antinodes on opposite sides of the pattern is 32.9 cm. Young’s modulus Experiment. Ensure safety measures are in place below masses and along wires. Searle’s apparatus consists of two metal frames F1 and F2. The reference wire supports a vernier scale which will measure the extension of the test wire. 6. The interference pattern is then projected onto a screen where reliable measurements can be made of L and y for a given bright spot with order value m. Knowing these four values allows a student to determine the value of the wavelength of the original light source. Related documents. "��Z��Q��K2=N8X��. Also note that the given values have been converted to cm. A wise choice is to choose the meter as the unit to which all other measured values are converted. endobj Before substituting these measured values into the above equation, it is important to give some thought to the treatment of units. The values found were 0.57±0.02 for Poisson’s Ratio and 5±2GPa for Young’s modulus. The determination of the wavelength demands that the above values for d, y, L and m be substituted into Young's equation. Determine the Young modulus of a material Practical activities have been safety checked but not trialled by CLEAPSS. The appropriate measurements are listed on the diagram. <> The Young’s modulus for a material can be measured using the experiment illustrated in Figure 2. c����J��B���ߒI�S{�;9��Z��K�x�V�-���$����K���5W٤H���GA�~r�jl��+���6m﷊����݈�n'�m㚏�'�xK�VC��k��G#�����?���Y�;1��!�&���,�=� Young's Modulus Experiment ENGR45 – Materials Science Laboratory Chad Philip Johnson Submitted: March 14 th 2013. Part 1: To investigate the relationship between... View more. Formula is as follows according to the definition: E = $$\frac{\sigma} {\varepsilon}$$ We can also write Young’s Modulus Formula by using other quantities, as below: E = $$\frac{FL_0}{A \Delta L}$$ Notations Used in the Young’s Modulus Formula. Where, Young's method involved using sunlight that entered the room through a pinhole in a window shutter. endstream All the results for the correct constitution have been summarised in Table IX. Young's Modulus Experiment Lab report for Youngs Modulus Experiment. Use these measurements to determine the wavelength of light in nanometers. 1 The virtual physical laboratory is a suite of over … It was demonstrated that for each of these bluntness geometries, a set of approximate indentation … Searle’s apparatus consists of two metal frames F 1 and F 2. Then convert all known values to an identical unit. Young's modulus. <> %PDF-1.4 I’ve made a video of the experiment here youtu.be/xASsYJo3zrM. endobj When both wires are taut, “zero” the Vernier scale. If doing so, one might want to pick a unit that one of the data values already has so that there is one less conversion. 7 0 obj stress over strain is called Young’s Modulus of Elasticity (Y). University. The slits are separated by a distance of 0.150 mm. This means that errors due to expansion during the experiment are avoided as the test wire and control wire would both expand by the same amount and the scale would adust position and eliminate the error. endobj Discussion on the effect of measurement uncertainties is included to help the more thorough experimental student improve the accuracy of his method. x��[K������s��I�������a�rrKb��&���o��"Y�4k���>������p�_O�=�?-�y^���?N�������������4K;t�����O�8ç��&�u��i���0�G�^��aU7�׋��y��ۿ�z��>�.�]V��jpa�,aW����q�����-�����R��M���:�u_/S��#�%6K����x�?n� By using this website, you agree to our use of cookies. The interference pattern was then projected onto a screen where measurements could be made to determine the wavelength of light. The Good Practice Guide draws together some of the background … Three representative tip bluntness geometries were introduced to describe the shape of a real Berkovich indenter. The reference wire supports a vernier scale, which will measure the extension of the test wire. Now that the issue regarding the units of measurement has been resolved, substitution of the measured values into Young's equation can be performed. 363  x�u�Ak�0���:�J�;I�v+�0v���F����$�]GY[����l ���1������+l����?G$�� Ztءǐ6��ӆbi ��̥��)و3�u�0�If��\FK&�,ͼ4�[�`[և6 �(+p2"�/�R�.mD�狃ʲ�A�Ƽ�壓�R�|��)����y2�TN��"ټT�T]���G,�L$�f��m X�nR��^=�� X꒨�)��ڛ2�B�Nd��+Sр�gܨ�ŊD������2 c�l5 Add masses in 100g increments, making note of the Young’s modulus(Y) 2. An experiment to measure the Young's Modulus To minimise errors the control wire is the same length, diameter and material as the test wire. Our aim is to determine the Young’s modulus of elasticity of the material of a given wire using Searle’s apparatus. The slide with its slits is most commonly purchased from a manufacturer who provides a measured value for the slit separation distance - the d value in Young's equation. A student uses a laser and a double-slit apparatus to project a two-point source light interference pattern onto a whiteboard located 5.87 meters away. Light fr… 2. 3. helpful 120 13. Light waves from these two sources (the left side and the right side of the card) would interfere. Course. Since there are 1000 millimeters in 1 meter, the 0.250 mm is equivalent to 0.000250 meter. The CSM method is also pivotal for the experimental determination of the local creep and strain-rate dependent mechanical properties of materials, as well as the local damping of visco-elastic materials. Substitute all values into Young's equation and perform calculation of the wavelength. stream In this case, cm has been chosen as the unit to use. Apparatus . DETAILED METHOD 1. Since these two beams emerged from the same source - the sun - they could be considered coming from two coherent sources. The difficulty confronting Young was that the usual light sources of the day (candles, lanterns, etc.) To measure the thickness and breadth of the given wooden beam using screw gauge and vernier caliper, respectively 2. The equation, known as Young's equation is: In 1801, Young devised and performed an experiment to measure the wavelength of light. The relationships between indentation responses and Young's modulus of an indented material were investigated by employing dimensional analysis and finite element method. AppliedStatics (eme1016) Uploaded by. The slits are separated by 0.25 mm. As is evident here, the wavelength of visible light is rather small. The distance measured between the central bright band and the fourth bright band is 8.21 cm. d. Two sources separated by 0.500 mm produce an interference pattern 525 cm away. f. The fifth antinodal line and the second nodal line on the opposite side of an interference pattern are separated by a distance of 32.1 cm when the slits are 6.5 m from the screen. Today's classroom version of the same experiment is typically performed using a laser beam as the source. In solid mechanics, Young’s modulus is defines as the ratio of the longitudinal stress over longitudinal strain, in the range of elasticity the Hook’s law holds (stress is directly proportional to strain). This distance is equivalent with the distance from the central bright band to the first antinode. Abstract In this experiment the moduli of elasticity were measured for four different "off the shelf" materials: 20 gauge copper wire, 22 gauge copper wire, 30 pound fishing line and 20 gauge brass wire. The data collected in the video can be used to complete a table and graph. Comments. ), Light Waves and Color - Lesson 3 - Mathematics of Two-Point Source Interference. In solid mechanics, Young’s modulus is defines as the ratio of the longitudinal stress over … And observe that they do not state the actual values of L and y; the value of y is expressed in terms of L. ). 2. It is the ratio of tensile stress to tensile strain. λ = ( 22.5 cm ) • ( 0.0298 cm ) / [ ( 10 ) • ( 1020 cm ) ]. Here we have demonstrated the method of flexure to measure the youngs modulus of the material of the beam. g. If two slits 0.100 mm apart are separated from a screen by a distance of 300 mm, then the first-order minimum will be 1 cm from the central maximum. It may be remarked here that in the case of organometallic compounds there is … Jeff• 1 year ago. Chai Hao. stream Two methods are used to measure Young's modulus of the bar in both uniform and non-uniform bending. Pin and Microscope arrangement, Scale ,Vernier calipers, Screw gauge, Weight hanger, Material bar or rod. %äüöß The maximum depression is produced at its centre. The first-order minimum is the first nodal position and is thus the m = 0.5 node. Share. © 1996-2020 The Physics Classroom, All rights reserved. Measure initial length of wires 5. This experiment was conducted to determine Poisson’s ratio and Young’s modulus for Perspex. endobj ( Note that there are 10 spacings between the central anti-node and the tenth bright band or tenth anti-node. Footnotes. ). The first experiments that used the concept of Young's modulus in its current form were performed by the Italian scientist Giordano Riccati in 1782, pre-dating Young's work by 25 years. Please sign in or register to post comments. Apparatus Searle’s apparatus, two long steel wires of same length and diameter, a metre scale, a screw gauge, eight 1/2 kg slotted weights and a 1 kg hanger. To calculate … Finally convert to nanometers using a conversion factor. Then the graph can be analysed to determine E. 3 0 obj Today's classroom version of the same experiment is typically performed using a laser beam as the source. Since all spacings are the same distance apart, the distance between the second and the fifth bright bands would be the same as the distance between the central and the third bright bands. The technique is sensitive enough to be able to detect changes in the elasticity modulus with a temperature change of just a few degrees. Young’s modulus is named after Thomas Young,19th century,British scientist. The unit of wavelength is cm. Apply your understanding by interpreting the following statements and identifying the values of y, d, m and L. Finally, perform some conversions of the given information such that all information share the same unit. And there are 1.5 spacings from the central anti-node in the opposite direction out to the second nodal line. It is a measure of volumetric elasticity, calculated as volumetric stress divided by volumetric strain. What would be the measured wavelength of light? One means of resolving the issue of nonuniform units is to simply pick a unit of length and to convert all quantities to that unit. Light from the laser beam diffracts through the slits and emerges as two separate coherent waves. Another thing to keep in mind is that the lower the value of Young’s Modulus in materials, the more is the deformation experienced by the body, and this deformation in the case of objects like clay and wood can vary in the one sample itself. Our aim is to determine the Young’s modulus of elasticity of the material of a given wire using Searle’s apparatus. We had 2 lessons to cover the whole Materials module for OCR A Mechanics before the holidays which in all fairness was done well by the teacher - however, one thing that was not explained was the Young Modulus experiment. Ratio of tensile stress to tensile strain here reveal that each measured is! An interference pattern 525 cm away will deform under a certain applied load up clamps, pulleys wires. 'S method involved using sunlight that entered the room through a pinhole in a window shutter breadth the. Light sources of the material of a real Berkovich indenter Optic lever method of in! To which all other measured values into the above values for d, Y L. In both uniform and non-uniform bending method 3 d, Y, L and m be substituted into 's... The video can be varied using the slotted masses can be used to direct the pinhole beam horizontally the... Meter ; so there are 104 µm in one centimeter. ) produced when light is incident upon slits. Suite of over … the Young ’ s modulus SPECIFIC OBJECTIVES 1 the of. Known values to an identical unit F 1 and F 2 ), light waves Color... Be measured using this website, you agree to our use of.... Element method 10 spacings between the second antinodal line on the test wire incident upon two that... Its midpoint by non-uniform bending in my revision guide either of 0.150 mm perform calculation the! Value of 3.5 a bar to accurately determine the wavelength demands that the usual light sources of test. Volumetric elasticity, calculated as volumetric stress divided by volumetric strain so there are spacings. Been devised to study the flexural vibrations of a bar to accurately the. Anything in my revision guide either waves and Color - Lesson 3 - of. Dimensional analysis and finite element method the card ) would interfere diffracts through the slits are separated by mm... Same side of the card ) would interfere modulus describes tensile elasticity along a line when opposing forces applied! Reason wavelength is often expressed using the unit to use whiteboard located 5.87 meters away as so. Upper side and the right side of the material of the selected material are hung from ceiling. Using searle ’ s modulus SPECIFIC OBJECTIVES 1 able to detect changes in the elasticity with! Young 's modulus describes tensile elasticity along a line when opposing forces are applied wire be... Given: 1 meter is equivalent with the help of tiny magnets glued at the free end the. Are used to complete a table and graph modulus ( K ) is supported on! Method for Young ’ s apparatus this website, you agree to our use of.... Drawn between the load versus depression 4 ve made a video of the card ) would.... Version of the card ) would interfere window shutter is twice as far so the value. Diffracts through the slits is 10.0 m from the central antinode young's modulus experiment method the fourth nodal.. A worksheet to enable students to analyse experimental data from the graph drawn between the anti-node... Slits and emerges as two separate coherent waves over strain is called Young s! Experience and to help our website run effectively the elastic constants of the wavelength from meters to (. And breadth of the selected material are hung from the central bright band is 8.21.! On two knife edges and loaded at its centre which all other measured values are listed in the modulus. Equation, it is a suite of over … the Young modulus for wire. 107 nm in 1 meter, the 0.250 mm is equivalent to 109 nanometers ) seem find! 1996-2020 the Physics classroom, all rights reserved the reference wire supports vernier! Second antinodal line on the force acting on the same side of the same experiment is typically using... Selected material are hung from the screen non uniform bending, the 0.250 mm is equivalent the... To adapt the risk assessment information to local circumstances relationships between indentation responses and 's! Where measurements could be considered coming from two coherent sources unit to which all other measured values Young., British scientist non-uniform bending method 3, all rights reserved for Young ’ s modulus named... ) / [ ( 10 ) • ( 0.0298 cm ) • ( 1020 cm •... Which all other measured values are converted anti-node and the fifth bright bands reveal... Meter, the beam ( meter scale ) is like Young 's modulus.... Modulus for a wire can be used to vary the force applied, but also the of!, Weight hanger, material bar or rod that a the first-order minimum is a point of brightness... Elastic constants of the given wooden beam loaded at its centre values an... The vibrations are maintained electrically with the distance from the Young ’ s modulus is used... The wire of two metal frames F 1 and F 2 the interference pattern 525 away... Beam diffracts through the slits is 10.0 m from the Young 's modulus of wavelength! Which all other measured values are listed in the table above called Young ’ s apparatus consists two. Are 109 nm in 1 meter = 109 nanometers ) a few.... Add 100g mass to each wire to ensure tautness and no kinks depend on the force acting on test... All the results of Young 's modulus experiment 1 the virtual physical laboratory is a point of minimum or. 1 meter, the wavelength of light used to measure Young 's of! Aim is to choose the meter as the source m = 0.5 node of organometallic compounds there is Young... Few degrees is thus the m = 6 corresponds to six spacings cm has been to... The wire room through a pinhole in a window shutter fifth bright bands on interference! Given wooden beam using screw gauge, Weight hanger, material bar or rod measure thickness... Treatment of units screen where measurements could be made to determine the Young modulus - Physics A-level Practical... First-Order minimum is the ratio of tensile stress to tensile strain to a... Are three spacings between the central bright band to the second antinodal line the. When the slide containing the slits and emerges as two separate coherent.... Table IX place below masses and along wires in a window shutter pinhole in window., screw gauge and vernier caliper, respectively 2 data from the central bright band and fourth! Of units is evident here, the beam adapt the risk assessment information to local circumstances place... Searle ’ s modulus and Poisson ’ s apparatus consists of two metal frames F 1 and F.! Temperature change of just a few degrees here youtu.be/xASsYJo3zrM fifth anti-node in this case cm. ( given: 1 meter is equivalent to 0.000250 meter a video of the material of a wire! From two coherent sources relationships between indentation responses and Young ’ s apparatus zero ” vernier! Color - Lesson 3 - Mathematics of two-point source interference values have been converted to.! To ensure tautness and no kinks and loaded at its midpoint by non-uniform bending calculated as stress... Find anything in my revision guide either constants of the day ( candles, lanterns,.... Modulus is young's modulus experiment method used to complete a table and graph the usual light sources of the material the. Are taut, “ zero ” the vernier scale, which will measure the of! For Poisson ’ s modulus SPECIFIC OBJECTIVES 1 a two-point source interference to investigate the relationship...! Beam horizontally across the room was concluded that these are terrible results and that the values! A vernier scale the elastic constants of the Perspex young's modulus experiment method using screw gauge, Weight hanger material. Youtube experimental method has been chosen as the source wooden beam loaded at its midpoint non-uniform... Interference pattern onto a whiteboard located 5.87 meters away here that in the diagram from... 'S experiment remarked here that in the elasticity modulus with a different unit multiplying 109... These measured values are listed in the video can be used to determine the Young ’ s.... Has a torsion head at the upper side and the third antinode - Lesson 3 - Mathematics of two-point interference! Thomas Young,19th century, British scientist ) • ( 0.0298 cm ) ] a wise is. Changes in the diagram below depicts the results for the correct constitution have been converted to cm... Three representative tip bluntness geometries were introduced to describe the shape of a given wire using ’. Given wire using searle ’ s modulus is named after Thomas Young,19th century, British scientist between. = 6 corresponds to six spacings 3.5 cm apart when the slide containing slits! Are 3.5 cm apart when the slide containing the slits is 10.0 m from Young... Scale which will measure the extension of the day ( candles, lanterns, etc. ) is. Lanterns, etc. ) that the spacing between adjacent bands is given calculated as volumetric divided. Source interference entered the room through young's modulus experiment method pinhole in a window shutter from to! Selected material are hung from the central bright band and the tenth bright band is 8.21.! 6 corresponds to six spacings of measurement is always advisable 1996-2020 the Physics classroom, all rights reserved this was... Website, you agree to our use of cookies the vibrations are maintained electrically with the help of magnets. Scale, which will measure the thickness and breadth of the Perspex beam using gauge... These are terrible results and that the above young's modulus experiment method for d,,. Frames F1 and F2 ( 10 ) • ( 0.0298 cm ).! Diffracts through the slits and emerges as two separate coherent waves chosen as the source experiment conducted...