Document that explains the chosen concept to the animator 1

MEISSNER EFFECT Authors: When a specimen is placed in a magnetic field and is then cooled through the transition temperature for superconductivity, the magnetic flux originally present is ejected from the specimen. This is called Meissner effect. Course Name: Superconductivity. Authors: Anura.B.Kenkre. 2

Learning Objectives After interacting with this Learning Object, the learner will be able to: Describe the changes occurring in the magnetic field lines when a normal metal placed in the magnetic field is cooled below its superconducting transition temperature. Identify that different metals have different transition temperatures. 3

1 2 3 4 5 Definitions of the components/Keywords: (For the user and to be included in the 'Let's learn-Definition Section') 1 Certain metals and alloys exhibit almost zero electrical resistivity when they are cooled to sufficiently low temperatures.This reduction in the value of electrical resistivity to zero is known as superconductivity. The temperature at which the transition to the superconducting state takes place is called the critical temperature(Tc)or the superconducting transition temperature. Magnetic field lines are the trajectories along which iron filings would align themselves if placed in a magnetic field. This concept is explained ahead in detail. 2 3 4 5 4 4

Definitions of the components/Keywords: (for user) continued… By spreading fine iron filings on a piece of paper laid on top of a magnet, you can see the outline of the magnetic field. The picture below shows the iron filings and compasses show the shape and direction of the magnetic field. The iron filings line up along the magnetic field lines of the magnet. Note the circular pattern of the field lines. and also note that more iron filings are attracted to the poles because the strength of the magnetic field is greater at the poles.

1 2 3 4 5 Definitions of the components/Keywords: (for the animator) The temperature at which the pattern of the magnetic field lines changes is called the critical temperature(Tc)or the superconducting transition temperature. Magnetic field lines are the curved lines between the two ends of the magnet. The picture below explains the idea: 2 3 4 5 6 6

Master layout or diagram INSTRUCTIONS SLIDE 1 Master layout or diagram Make a schematic diagram of the concept Explain to the animator about the beginning and ending of the process. Draw image big enough for explaining. In above image, identify and label different components of the process/phenomenon. (These are like characters in a film)‏ Illustrate the basic flow of action by using arrows. Use BOLD lines in the diagram, (minimum 2pts.)‏ In the slide after that, provide the definitions of ALL the labels used in the diagram 2 3 4 5 7

Master layout or diagram INSTRUCTIONS SLIDE 1 Master layout or diagram You may have multiple master layouts. In this case, number the master layout. ( e.g. Master layout 1)‏ Each Master layout should be followed by the stepwise description of the animation stages related to it. 2 3 4 5 8

1 Explain the process 2 In this step, use an example to explain the concept. It can be an analogy, a scenario, or an action which explains this concept/process/topic Try to use examples from day-to-day life to make it more clear You have to describe what steps the animator should take to make your concept come alive as a series of moving images. Keep the examples simple to understand, and also to illustrate/animate. 3 4 5 9

2 Scenario / Action: 1 3 4 5 OVERVIEW: A metal (selected from the drop-down menu) is placed near a bar magnet. Above the superconducting transition temperature, the magnetic field lines created by the bar magnet go through the metal. Depending upon the metal selected, at its corresponding transition temperature, there suddenly are no magnetic field lines in the interior of the metal. Furthermore, the magnetic field lines go around the metal on the outside. 3 4 5 10

Stepwise description of process 1 The goal of the document is to provide instructions to an animator who is not a expert. You have to describe what steps the animator should take to make your concept come alive as a moving visualization. Use one slide per step. This will ensure clarity of the explanation. Add a image of the step in the box, and the details in the table below the box. You can use any images for reference, but mention about it's copyright status The animator will have to re-draw / re-create the drawings Add more slides as per the requirement of the animation 2 3 4 5 11

3 Master Layout 1 1 2 4 5 Al 12 12 Magnetic field lines Metal (Fig for reference of the magnetic lines for the animator.) 3 Magnet Al 4 Fig 1 Fig 2 5 12 12

3 Step 1: 1 2 4 5 Fig 1 (This figure is for refrence of animator.) T1: Select a material (This figure is for refrence of animator.) 2 3 Fig 1 Interactivit y type (IO 1/IO 2) Instruction to learners Boundary limits & options Instruction to animators Results and output Drop down for selection of metal Select a metal from the drop down menu. Options: Metal and its symbols: Aluminium,Symbol Al Copper, Symbol Cu Lead, Symbol Pb Niobium, Symbol Nb Show the magnet in figure 1 with its magnetic field lines. (refer to fig 1.) Show a default metal Al as shown in fig 1. After they choose a metal go to step no 2,3,4 or 5 depending on the metal chosen. If the learner selects a metal from the drop down the symbol should appear in metal in fig 1. E.g if learner chooses lead then symbol Pb should come in the metal in fig 1. - If learner selects Aluminium go to step 2 If learner selects copper go to step 3 If learner selects lead go to step 4 If learner selects niobium go to step 5 4 5 13

3 Master layout 2 1 2 4 5 TEMPERATURE SCALES: Tc(K) Tc(K) LOW TEMPERATURE SCALE: DATA BOX 0.1 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 (In the data box for low temperature scale, display values up to 1 decimal place .Just display the values, do not include the heading of ‘data box': This instruction is for reference of animator, not to be shown on screen) 3 (In the data box for high temperature scale, display values up to difference of 10 units. Just display the values, do not include the heading of ‘data box’:This instruction is for reference of animator, not to be shown on screen) HIGH TEMPERATURE SCALE: Tc(K) DATA BOX 4 10 100 200 300 400 500 600 700 800 900 1000 (Room temperature) Note:(Include a reset button as one of the controls.) RESET BUTTON: 5 14 14

3 Step 2: 1 2 4 5 Tc(K) Tc(K) LOW TEMPERATURE SCALE T1: Vary the temperature of Aluminium metal Tc(K) LOW TEMPERATURE SCALE 0.1 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 Al 2 HIGH TEMPERATURE SCALE Tc(K) 10 100 200 300 400 500 600 700 800 900 1000 (Room temperature) 3 Fig 1 Fig 2 Fig 3 Interactivit y type (IO 1/IO 2) Instruction to learners Boundary limits & options Instruction to animators Results and output Two slider bars for temperature: High temperature scale: 1) 10K-1000K Low temperature scale: 2) 0.1K-10.0K. Include a radio button next to each scale so that user can select which scale he/she wants to use. Choose a scale by clicking on the radio buton and vary the temperature. Options:1) Scale 1: 10 – 1000K. In the text box beside the scale,allow values with difference of ten units. Eg: 10,20,30,40,etc, as user slides the bar. 2) Scale 2: 0.1K- 10.0K. In the text box beside the scale,allow values with 1 decimal place. Eg: 0.1,0.2,etc, as user slides the bar. (Master layout 2) Show only that scale which is chosen by the learner. Show fig 1 with the aluminium metal symbol. Show the red arrow in the temperature scale to denote room temperature at 300K. Allow learner to vary temperature every 10th unit between 10-100, 100-200 and so on. As the learner varies the temperature show the red arrow moving accordingly and the temperature value displayed in the text box beside the scale. At 1.2K,the field lines change and become like those shown in Fig 2. At temperatures below 1.2K,the field lines should remain like those shown in Fig2. If user clicks on reset button go to step 1. If the learner chooses a temperature that is lesser than or equal to 1.2K then show fig 1 magnetic field lines changing and becoming like fig 2. If the learner chooses any other temperature above 1.2K ,show fig 1 only. 4 5 15

3 Step 3: 1 2 4 5 Tc(K) Tc(K) LOW TEMPERATURE SCALE T1: Vary the temperature of Copper metal Tc(K) LOW TEMPERATURE SCALE 0.1 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 2 Cu HIGH TEMPERATURE SCALE Tc(K) 10 100 200 300 400 500 600 700 800 900 1000 (Room temperature) 3 Fig 1 Fig 3 Interactivit y type (IO 1/IO 2) Instruction to learners Boundary limits & options Instruction to animators Results and output Two slider bars for temperature: High temperature scale: 1) 10K-1000K Low temperature scale: 2) 0.1K-10.0K. Include a radio button next to each scale so that user can select which scale he/she wants to use. Choose a scale by clicking on the radio buton and vary the temperature. Options:1) Scale 1: 10 – 1000K. In the text box beside the scale,allow values with difference of ten units. Eg: 10,20,30,40,etc, as user slides the bar. 2) Scale 2: 0.1K- 10.0K. In the text box beside the scale,allow values with 1 decimal place. Eg: 0.1,0.2,etc, as user slides the bar. (Master layout 2) Show only that scale which is chosen by the learner. Show fig 1 with the copper metal symbol. Show the red arrow in the temperature scale to denote room temperature at 300K. Allow learner to vary temperature every 10th unit between 10-100, 100-200 and so on. As the learner varies the temperature show the red arrow moving accordingly and the temperature value displayed in the text box beside the scale. Which ever temperature the learner chooses show fig 1 only. If user clicks on reset button,go to step 1. Which ever temperature the learner chooses show fig 1 only. 4 5 16

3 Step 4: 1 2 4 5 Tc(K) Tc(K) LOW TEMPERATURE SCALE T1: Vary the temperature of Lead metal LOW TEMPERATURE SCALE Tc(K) 0.1 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 Pb 2 Pb HIGH TEMPERATURE SCALE Tc(K) 10 100 200 300 400 500 600 700 800 900 1000 3 (Room temperature) Fig 1 Fig 2 Fig 3 Interactivit y type (IO 1/IO 2) Instruction to learners Boundary limits & options Instruction to animators Results and output Two slider bars for temperature: High temperature scale: 1) 10K-1000K Low temperature scale: 2) 0.1K-10.0K. Include a radio button next to each scale so that user can select which scale he/she wants to use. Choose a scale by clicking on the radio buton and vary the temperature. Options:1) Scale 1: 10 – 1000K. In the text box beside the scale,allow values with difference of ten units. Eg: 10,20,30,40,etc, as user slides the bar. 2) Scale 2: 0.1K- 10.0K. In the text box beside the scale,allow values with 1 decimal place. Eg: 0.1,0.2,etc, as user slides the bar. (Master layout 2) Show only that scale which is chosen by the learner. Show fig 1 with the lead metal symbol. Show the red arrow in the temperature scale to denote room temperature at 300K. Allow learner to vary temperature every 10th unit between 10-100, 100-200 and so on. As the learner varies the temperature show the red arrow moving accordingly and the temperature value displayed in the text box beside the scale. At 7.2K,the field lines change and become like those shown in Fig 2. At temperatures below 7.2K,the field lines should remain like those shown in Fig2. If user clicks on reset button,go to step 1. If the learner chooses a temperature that is lesser than or equal to 7.2K then show fig 1 magnetic field lines changing and becoming like fig 2. If the learner chooses any other temperature above 7.2K show fig 1 only. 4 5 17

3 Step 5: 1 2 4 5 Tc(K) Tc(K) LOW TEMPERATURE SCALE T1: Vary the temperature of Lead metal LOW TEMPERATURE SCALE Tc(K) 0.1 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 Nb 2 Nb HIGH TEMPERATURE SCALE Tc(K) 10 100 200 300 400 500 600 700 800 900 1000 3 (Room temperature) Fig 1 Fig 2 Fig 3 Interactivit y type (IO 1/IO 2) Instruction to learners Boundary limits & options Instruction to animators Results and output Two slider bars for temperature: High temperature scale: 1) 10K-1000K Low temperature scale: 2) 0.1K-10.0K. Include a radio button next to each scale so that user can select which scale he/she wants to use. Choose a scale by clicking on the radio buton and vary the temperature. Options:1) Scale 1: 10 – 1000K. In the text box beside the scale,allow values with difference of ten units. Eg: 10,20,30,40,etc, as user slides the bar. 2) Scale 2: 0.1K- 10.0K. In the text box beside the scale,allow values with 1 decimal place. Eg: 0.1,0.2,etc, as user slides the bar. (Master layout 2) Show only that scale which is chosen by the learner. Show fig 1 with the Niobium metal symbol. Show the red arrow in the temperature scale to denote room temperature at 300K. Allow learner to vary temperature every 10th unit between 10-100, 100-200 and so on. As the learner varies the temperature show the red arrow moving accordingly and the temperature value displayed in the text box beside the scale. At 9.3K,the field lines change and become like those shown in Fig 2. At temperatures below 9.3K,the field lines should remain like those shown in Fig2. If user clicks on reset button,go to step 1. If the learner chooses a temperature that is lesser than or equal to 9.3K then show fig 1 magnetic fields changing and becoming like fig 2. If the learner chooses any other temperature above 9.3K show fig 1 only. 4 5 18

3 1 2 4 5 Step 6: Pop up displaying: If user changes metal after selecting temperature scale. 2 3 Instructions for the animator Instruction to the learner Results and Output Boundary limits Interactivity type (IO1/IO2..)‏ Please press reset first,then change metal. 4 If user changes metal after selecting temperature scale,do not allow change and show pop up with instruction to learner. Pop up displaying: Please press reset first,then change metal. 5 19

Animation design 1 Please see the design template provided in the next slide. This is a sample template, and you are free to change as per your design requirements. Try and recreate the sections/subsections as shown in the template. 2 3 4 5 20

Aluminium (Al) Copper(Cu) Lead(Pb) Niobium(Nb) Select a metal‏: Credits What will you learn Play/pause Restart Lets Learn! Definitions Select a metal‏: Concepts Aluminium (Al) Assumptions (if any)‏ Animation Area Copper(Cu) Formula with derivation (if any)‏ Lead(Pb) Graphs/Diagram (for reference)‏ Test your understanding (questionnaire)‏ Niobium(Nb) Lets Sum up (summary)‏ LOW TEMPERATURE SCALE Tc(K) Want to know more… (Further Reading)‏ 0.1 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 HIGH TEMPERATURE SCALE Tc(K) 10 100 200 300 400 500 600 700 800 900 1000 (Room temperature) Output result of interactivity (if any)‏ Instructions/ Working area 21

Interactivity and Boundary limits 1 Interactivity and Boundary limits In this section, you will add the ‘Interactivity’ options to the animation. Use the template in the next slide to give the details. Insert the image of the step/s (explained earlier in the Section 3) in the box, and provide the details in the table below. The details of Interactivity could be: Types: Drop down, Slider bar, Data inputs etc. Options: Select one, Multiple selections etc Boundary Limits: Values of the parameters, which won’t show results after a particular point Results: Explain the effect of the interaction in this column Add more slides if necessary 2 3 4 5 22

3 1 2 4 5 Interactivity option 1: Step No: See slides 11 and 13 to16 Instructions for the animator Instruction to the learner Results and Output Boundary limits Interactivity type (IO1/IO2..)‏ 4 5 23

Self- Assessment Questionnaire for Learners INSTRUCTIONS SLIDE Self- Assessment Questionnaire for Learners Please provide a set of questions that a user can answer based on the LO. They can be of the following types: These questions should be 5 in number and can be of objective type (like MCQ, Match the columns, Yes or No, Sequencing, Odd One Out). The questions can also be open-ended. The user would be asked to think about the question. The author is requested to provide hints if possible, but a full answer is not necessary. One can include questions, for which the user will need to interact with the LO (with certain parameters) in order to answer it. 24

4 1 2 3 5 MULTIPLE CHOICE QUESTIONS: Questionnaire for users to test their understanding : 1 SOMETHING TO THINK ABOUT: Can you think of a situation when electric field lines do not penetrate a material when it is placed in an electric field? 2 MULTIPLE CHOICE QUESTIONS: 1. which material had the lowest Tc? Answers: a) aluminium b) copper c)lead d)‏niobium 2. Which of the following metals have not been observed to show Meissner Effect? Answers: a) aluminium b) copper c) lead d)‏niobium 3.What is the highest value of Tc you observed? Enter your answer: 3 4 Correct Answers: Answers: 1)a 2)b 3)9.3K Feedback: If user clicks correct answer then display “Correct!Make sure you can explain the reasoning!” If user clicks incorrect answer then display “Play with the simulation and Try again!” 5 25

Links for further reading Reference websites: http://www.ornl.gov/info/reports/m/ornlm3063r1/pt3.html http://www.howstuffworks.com/question610.htm http://en.wikipedia.org/wiki/Superconductivity#Meissner_effect Books: Introduction to Solid state physics-Charles Kittel(chapter 12) Solid state physics-MA Wahab.(chapter 17) Solid state physics-Ashcroft/Mermin. (Chapter 34) 26

INSTRUCTIONS SLIDE Summary Please provide points to remember to understand the concept/ key terms of the animation The summary will help the user in the quick review of the concept. 27

Summary The reduction in the value of electrical resistivity to zero is known as Superconductivity. The temperature at which the transition takes place in the absence of magnetic field is called the critical temperature(Tc)or the transition temperature. Tc is found to be different for different substances. The phenomenon in which at the transition temperature,a superconductor expels magnetic flux completely is called Meissner effect. 28