The Story of Π
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Arnold Sommerfeld in Einigen Zitaten Von Ihm Und Über Ihn1
K.-P. Dostal, Arnold Sommerfeld in einigen Zitaten von ihm und über ihn Seite 1 Karl-Peter Dostal, Arnold Sommerfeld in einigen Zitaten von ihm und über ihn1 Kurze biographische Bemerkungen Arnold Sommerfeld [* 5. Dezember 1868 in Königsberg, † 26. April 1951 in München] zählt neben Max Planck, Albert Einstein und Niels Bohr zu den Begründern der modernen theoretischen Physik. Durch die Ausarbeitung der Bohrschen Atomtheorie, als Lehrbuchautor (Atombau und Spektrallinien, Vorlesungen über theoretische Physik) und durch seine „Schule“ (zu der etwa die Nobelpreisträger Peter Debye, Wolfgang Pauli, Werner Heisenberg und Hans Bethe gehören) sorgte Sommerfeld wie kein anderer für die Verbreitung der modernen Physik.2 Je nach Auswahl könnte Sommerfeld [aber] nicht nur als theoretischer Physiker, sondern auch als Mathematiker, Techniker oder Wissenschaftsjournalist porträtiert werden.3 Als Schüler der Mathematiker Ferdinand von Lindemann, Adolf Hurwitz, David Hilbert und Felix Klein hatte sich Sommerfeld zunächst vor allem der Mathematik zugewandt (seine erste Professur: 1897 - 1900 für Mathematik an der Bergakademie Clausthal). Als Professor an der TH Aachen von 1900 - 1906 gewann er zunehmendes Interesse an der Technik. 1906 erhielt er den seit Jahren verwaisten Lehrstuhl für theoretische Physik in München, an dem er mit wenigen Unterbrechungen noch bis 1940 (und dann wieder ab 19464) unterrichtete. Im Gegensatz zur etablierten Experimen- talphysik war die theoretische Physik anfangs des 20. Jh. noch eine junge Disziplin. Sie wurde nun zu -
Finding Pi Project
Name: ________________________ Finding Pi - Activity Objective: You may already know that pi (π) is a number that is approximately equal to 3.14. But do you know where the number comes from? Let's measure some round objects and find out. Materials: • 6 circular objects Some examples include a bicycle wheel, kiddie pool, trash can lid, DVD, steering wheel, or clock face. Be sure each object you choose is shaped like a perfect circle. • metric tape measure Be sure your tape measure has centimeters on it. • calculator It will save you some time because dividing with decimals can be tricky. • “Finding Pi - Table” worksheet It may be attached to this page, or on the back. What to do: Step 1: Choose one of your circular objects. Write the name of the object on the “Finding Pi” table. Step 2: With the centimeter side of your tape measure, accurately measure the distance around the outside of the circle (the circumference). Record your measurement on the table. Step 3: Next, measure the distance across the middle of the object (the diameter). Record your measurement on the table. Step 4: Use your calculator to divide the circumference by the diameter. Write the answer on the table. If you measured carefully, the answer should be about 3.14, or π. Repeat steps 1 through 4 for each object. Super Teacher Worksheets - www.superteacherworksheets.com Name: ________________________ “Finding Pi” Table Measure circular objects and complete the table below. If your measurements are accurate, you should be able to calculate the number pi (3.14). Is your answer name of circumference diameter circumference ÷ approximately circular object measurement (cm) measurement (cm) diameter equal to π? 1. -
Evaluating Fourier Transforms with MATLAB
ECE 460 – Introduction to Communication Systems MATLAB Tutorial #2 Evaluating Fourier Transforms with MATLAB In class we study the analytic approach for determining the Fourier transform of a continuous time signal. In this tutorial numerical methods are used for finding the Fourier transform of continuous time signals with MATLAB are presented. Using MATLAB to Plot the Fourier Transform of a Time Function The aperiodic pulse shown below: x(t) 1 t -2 2 has a Fourier transform: X ( jf ) = 4sinc(4π f ) This can be found using the Table of Fourier Transforms. We can use MATLAB to plot this transform. MATLAB has a built-in sinc function. However, the definition of the MATLAB sinc function is slightly different than the one used in class and on the Fourier transform table. In MATLAB: sin(π x) sinc(x) = π x Thus, in MATLAB we write the transform, X, using sinc(4f), since the π factor is built in to the function. The following MATLAB commands will plot this Fourier Transform: >> f=-5:.01:5; >> X=4*sinc(4*f); >> plot(f,X) In this case, the Fourier transform is a purely real function. Thus, we can plot it as shown above. In general, Fourier transforms are complex functions and we need to plot the amplitude and phase spectrum separately. This can be done using the following commands: >> plot(f,abs(X)) >> plot(f,angle(X)) Note that the angle is either zero or π. This reflects the positive and negative values of the transform function. Performing the Fourier Integral Numerically For the pulse presented above, the Fourier transform can be found easily using the table. -
History of the Numerical Methods of Pi
History of the Numerical Methods of Pi By Andy Yopp MAT3010 Spring 2003 Appalachian State University This project is composed of a worksheet, a time line, and a reference sheet. This material is intended for an audience consisting of undergraduate college students with a background and interest in the subject of numerical methods. This material is also largely recreational. Although there probably aren't any practical applications for computing pi in an undergraduate curriculum, that is precisely why this material aims to interest the student to pursue their own studies of mathematics and computing. The time line is a compilation of several other time lines of pi. It is explained at the bottom of the time line and further on the worksheet reference page. The worksheet is a take-home assignment. It requires that the student know how to construct a hexagon within and without a circle, use iterative algorithms, and code in C. Therefore, they will need a variety of materials and a significant amount of time. The most interesting part of the project was just how well the numerical methods of pi have evolved. Currently, there are iterative algorithms available that are more precise than a graphing calculator with only a single iteration of the algorithm. This is a far cry from the rough estimate of 3 used by the early Babylonians. It is also a different entity altogether than what the circle-squarers have devised. The history of pi and its numerical methods go hand-in-hand through shameful trickery and glorious achievements. It is through the evolution of these methods which I will try to inspire students to begin their own research. -
MATLAB Examples Mathematics
MATLAB Examples Mathematics Hans-Petter Halvorsen, M.Sc. Mathematics with MATLAB • MATLAB is a powerful tool for mathematical calculations. • Type “help elfun” (elementary math functions) in the Command window for more information about basic mathematical functions. Mathematics Topics • Basic Math Functions and Expressions � = 3�% + ) �% + �% + �+,(.) • Statistics – mean, median, standard deviation, minimum, maximum and variance • Trigonometric Functions sin() , cos() , tan() • Complex Numbers � = � + �� • Polynomials = =>< � � = �<� + �%� + ⋯ + �=� + �=@< Basic Math Functions Create a function that calculates the following mathematical expression: � = 3�% + ) �% + �% + �+,(.) We will test with different values for � and � We create the function: function z=calcexpression(x,y) z=3*x^2 + sqrt(x^2+y^2)+exp(log(x)); Testing the function gives: >> x=2; >> y=2; >> calcexpression(x,y) ans = 16.8284 Statistics Functions • MATLAB has lots of built-in functions for Statistics • Create a vector with random numbers between 0 and 100. Find the following statistics: mean, median, standard deviation, minimum, maximum and the variance. >> x=rand(100,1)*100; >> mean(x) >> median(x) >> std(x) >> mean(x) >> min(x) >> max(x) >> var(x) Trigonometric functions sin(�) cos(�) tan(�) Trigonometric functions It is quite easy to convert from radians to degrees or from degrees to radians. We have that: 2� ������� = 360 ������� This gives: 180 � ������� = �[�������] M � � �[�������] = �[�������] M 180 → Create two functions that convert from radians to degrees (r2d(x)) and from degrees to radians (d2r(x)) respectively. Test the functions to make sure that they work as expected. The functions are as follows: function d = r2d(r) d=r*180/pi; function r = d2r(d) r=d*pi/180; Testing the functions: >> r2d(2*pi) ans = 360 >> d2r(180) ans = 3.1416 Trigonometric functions Given right triangle: • Create a function that finds the angle A (in degrees) based on input arguments (a,c), (b,c) and (a,b) respectively. -
Perimeter, Area, and Volume
Perimeter, Area, and Volume Perimeter is a measurement of length. It is the distance around something. We use perimeter when building a fence around a yard or any place that needs to be enclosed. In that case, we would measure the distance in feet, yards, or meters. In math, we usually measure the perimeter of polygons. To find the perimeter of any polygon, we add the lengths of the sides. 2 m 2 m P = 2 m + 2 m + 2 m = 6 m 2 m 3 ft. 1 ft. 1 ft. P = 1 ft. + 1 ft. + 3 ft. + 3 ft. = 8 ft. 3ft When we measure perimeter, we always use units of length. For example, in the triangle above, the unit of length is meters. For the rectangle above, the unit of length is feet. PRACTICE! 1. What is the perimeter of this figure? 5 cm 3.5 cm 3.5 cm 2 cm 2. What is the perimeter of this figure? 2 cm Area Perimeter, Area, and Volume Remember that area is the number of square units that are needed to cover a surface. Think of a backyard enclosed with a fence. To build the fence, we need to know the perimeter. If we want to grow grass in the backyard, we need to know the area so that we can buy enough grass seed to cover the surface of yard. The yard is measured in square feet. All area is measured in square units. The figure below represents the backyard. 25 ft. The area of a square Finding the area of a square: is found by multiplying side x side. -
Rectangles with the Same Numerical Area and Perimeter
Rectangles with the Same Numerical Area and Perimeter About Illustrations: Illustrations of the Standards for Mathematical Practice (SMP) consist of several pieces, including a mathematics task, student dialogue, mathematical overview, teacher reflection questions, and student materials. While the primary use of Illustrations is for teacher learning about the SMP, some components may be used in the classroom with students. These include the mathematics task, student dialogue, and student materials. For additional Illustrations or to learn about a professional development curriculum centered around the use of Illustrations, please visit mathpractices.edc.org. About the Rectangles with the Same Numerical Area and Perimeter Illustration: This Illustration’s student dialogue shows the conversation among three students who are trying to find all rectangles that have the same numerical area and perimeter. After trying different rectangles of specific dimensions, students finally develop an equation that describes the relationship between the width and length of a rectangle with equal area and perimeter. Highlighted Standard(s) for Mathematical Practice (MP) MP 1: Make sense of problems and persevere in solving them. MP 2: Reason abstractly and quantitatively. MP 7: Look for and make use of structure. MP 8: Look for and express regularity in repeated reasoning. Target Grade Level: Grades 8–9 Target Content Domain: Creating Equations (Algebra Conceptual Category) Highlighted Standard(s) for Mathematical Content A.CED.A.2 Create equations in two or more variables to represent relationships between quantities; graph equations on coordinate axes with labels and scales. A.CED.A.4 Rearrange formulas to highlight a quantity of interest, using the same reasoning as in solving equations. -
Area and Perimeter What Is the Formula for Perimeter and How Is It Applied in Construction?
Name: Basic Carpentry Coop Tech Morning/Afternoon Canarsie HS Campus Mr. Pross Finding Area and Perimeter What is the formula for perimeter and how is it applied in construction? 1. Perimeter: The perimeter of a rectangle is the distance around it. Therefore, the perimeter is the sum of all four sides. Perimeter is important when calculating estimates for materials needed for completing a job. Example: Before ordering baseboard trim, the must wrap around the entire room, the perimeter of a 12’ 12 ft x 18 ft room must be found. What is the perimeter of the room? 18’ What is the formula for perimeter? Write it below. _______________________ 1. This is the formula you will need to follow in order to calculate area. = 2 (12 ft + 18 ft) 2. Add the length and width in parentheses. The length plus the width represent halfway around the room. = 2 (30 ft) 3. Multiply the sum of the length and width by 2 to find the entire distance around. = 60 ft. Practice A client asked that you to install a new window. The framing though is too small and you need to demolish it and rebuild it. First you need to find the perimeter of the window. If this window measures 32 inches by 42 inches, what is the perimeter? Name: Basic Carpentry Coop Tech Morning/Afternoon Canarsie HS Campus Mr. Pross 2. Area: The area of a square is the surface included within a set of lines. In carpentry, this means the total space of a room or even a building. Area, like permiter, is an important mathematical formula for estimating material and cost in construction. -
36 Surprising Facts About Pi
36 Surprising Facts About Pi piday.org/pi-facts Pi is the most studied number in mathematics. And that is for a good reason. The number pi is an integral part of many incredible creations including the Pyramids of Giza. Yes, that’s right. Here are 36 facts you will love about pi. 1. The symbol for Pi has been in use for over 250 years. The symbol was introduced by William Jones, an Anglo-Welsh philologist in 1706 and made popular by the mathematician Leonhard Euler. 2. Since the exact value of pi can never be calculated, we can never find the accurate area or circumference of a circle. 3. March 14 or 3/14 is celebrated as pi day because of the first 3.14 are the first digits of pi. Many math nerds around the world love celebrating this infinitely long, never-ending number. 1/8 4. The record for reciting the most number of decimal places of Pi was achieved by Rajveer Meena at VIT University, Vellore, India on 21 March 2015. He was able to recite 70,000 decimal places. To maintain the sanctity of the record, Rajveer wore a blindfold throughout the duration of his recall, which took an astonishing 10 hours! Can’t believe it? Well, here is the evidence: https://twitter.com/GWR/status/973859428880535552 5. If you aren’t a math geek, you would be surprised to know that we can’t find the true value of pi. This is because it is an irrational number. But this makes it an interesting number as mathematicians can express π as sequences and algorithms. -
Double Factorial Binomial Coefficients Mitsuki Hanada Submitted in Partial Fulfillment of the Prerequisite for Honors in The
Double Factorial Binomial Coefficients Mitsuki Hanada Submitted in Partial Fulfillment of the Prerequisite for Honors in the Wellesley College Department of Mathematics under the advisement of Alexander Diesl May 2021 c 2021 Mitsuki Hanada ii Double Factorial Binomial Coefficients Abstract Binomial coefficients are a concept familiar to most mathematics students. In particular, n the binomial coefficient k is most often used when counting the number of ways of choosing k out of n distinct objects. These binomial coefficients are well studied in mathematics due to the many interesting properties they have. For example, they make up the entries of Pascal's Triangle, which has many recursive and combinatorial properties regarding different columns of the triangle. Binomial coefficients are defined using factorials, where n! for n 2 Z>0 is defined to be the product of all the positive integers up to n. One interesting variation of the factorial is the double factorial (n!!), which is defined to be the product of every other positive integer up to n. We can use double factorials in the place of factorials to define double factorial binomial coefficients (DFBCs). Though factorials and double factorials look very similar, when we use double factorials to define binomial coefficients, we lose many important properties that traditional binomial coefficients have. For example, though binomial coefficients are always defined to be integers, we can easily determine that this is not the case for DFBCs. In this thesis, we will discuss the different forms that these coefficients can take. We will also focus on different properties that binomial coefficients have, such as the Chu-Vandermonde Identity and the recursive relation illustrated by Pascal's Triangle, and determine whether there exists analogous results for DFBCs. -
Perimeter , Area and Volume with Changed Dimensions
Perimeter , Area and Volume with changed dimensions Given a rectangle with dimensions of 6 by 4. Perimeter: __________ Area: ______________ Double the dimensions of the rectangle (multiply each side by 2) New Perimeter: ___________ New Area: _______________ Compare the effects on the perimeter and area when dimensions of a shape are changed (dilated) proportionally. Complete the chart below: Smaller Larger Ratio of larger Rectangle Rectangle dimension to smaller dimension Length Width Perimeter Area Conclusion: Perimeter , Area and Volume with changed dimensions If the dimensions of the rectangle are doubled (scale factor of 2): the perimeter is___________ If the dimensions of the rectangles are doubled (scale factor of 2): the area is ____________ Extension: If the dimensions of the rectangle are tripled (scale factor of 3): the perimeter is ______________ If the dimensions of the rectangle are triples (scale factor of 3): the area is ___________________ What do you think will happen to volume when dimensions are changed proportionally? Given a rectangular prism with dimensions of 6 by 4 by 2: Volume: _____________ Double the dimensions of the prism: New Volume: __________ Perimeter , Area and Volume with changed dimensions Smaller Rectangle Larger Rectangle Ratio of larger dimension to smaller dimension Length Width Height Volume Since each dimension was dilated (multiplied) by 2, then the volume was multiplied by 8: or 23 (scale factor cubed) Why do you think the volume is “cubed”? Perimeter , Area and Volume with changed dimensions Effects on perimeter, area and volume when dimensions of a shape are changed proportionally: Original Scale factor Perimeter Area Volume times 2 times 2=___ times 22=___ times 23=___ times 3 times 4 1 times 2 2 times 3 3 times 4 Examples: 1. -
Slides from These Events
The wonderπ of March 14th, 2019 by Chris H. Rycroft Harvard University The circle Radius r Area = πr2 Circumference = 2πr The wonder of pi • The calculation of pi is perhaps the only mathematical problem that has been of continuous interest from antiquity to present day • Many famous mathematicians throughout history have considered it, and as such it provides a window into the development of mathematical thought itself Assumed knowledge 3 + = Hindu–Arabic Possible French origin Welsh origin 1st–4th centuries 14th century 16th century • Many symbols and thought processes that we take for granted are the product of millennia of development • Early explorers of pi had no such tools available An early measurement • Purchased by Henry Rhind in 1858, in Luxor, Egypt • Scribed in 1650BCE, and copied from an earlier work from ~ 2000BCE • One of the oldest mathematical texts in existence • Consists of fifty worked problems, the last of which gives a value for π Problem 24 (An example of Egyptian mathematical logic) A heap and its 1/7 part become 19. What is the heap? Then 1 heap is 7. (Guess an answer and see And 1/7 of the heap is 1. if it works.) Making a total of 8. But this is not the right answer, and therefore we must rescale 7 by the (Re-scale the answer to obtain the correct solution.) proportion of 19/8 to give 19 5 7 × =16 8 8 Problem 24 A heap and its 1/7 part become 19. What is the heap? • Modern approach using high-school algebra: let x be the size of the heap.