A simple transformation with remarkable properties was used by Nikolai Zhukovsky around 1910 to study the flow around aircraft wings. It is defined by $latex \displaystyle \omega = \textstyle{\frac{1}{2}}\displaystyle{\left(z +\frac{1}{z}\right)} &fg=000000$ and is usually called the Joukowsky Map. We begin with a discussion of the theory of fluid flow in two dimensions. Readers familiar with … Continue reading Zhukovsky’s Airfoil
Month: February 2020
How many numbers begin with a 1? More than 30%!
The irregular distribution of the first digits of numbers in data-bases provides a valuable tool for fraud detection. A remarkable rule that applies to many datasets was accidentally discovered by an American physicist, Frank Benford, who described his discovery in a 1938 paper, "The Law of Anomalous Numbers" [TM181 or search for “thatsmaths” at irishtimes.com]. … Continue reading How many numbers begin with a 1? More than 30%!
A Ring of Water Shows the Earth’s Spin
Around 1913, while still an undergraduate, American physicist Arthur Compton described an experiment to demonstrate the rotation of the Earth using a simple laboratory apparatus. Compton (1892--1962) won the Nobel Prize in Physics in 1927 for his work on scattering of EM radiation. This phenomenon, now called the Compton effect, confirmed the particle nature of … Continue reading A Ring of Water Shows the Earth’s Spin
Using Maths to Reduce Aircraft Noise
If you have ever tried to sleep under a flight-path near an airport, you will know how serious the problem of aircraft noise can be. Aircraft noise is amongst the loudest sounds produced by human activities. The noise is over a broad range of frequencies, extending well beyond the range of hearing. The problem of … Continue reading Using Maths to Reduce Aircraft Noise
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