Tag Archives: Engineering

Electron uncertainty

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daisyMost of us are uncomfortable with uncertainty.  Michael Faraday’s ability to ‘accept the given – certainties and uncertainties’ [see my post entitled ‘Steadiness and placidity’ on July 18th, 2016] was exceptional and perhaps is one reason he was able to make such outstanding contributions to science and engineering.  It has been said that his ‘Expts. on the production of Electricity from Magnetism, etc. etc.’ [Note 148 from Faraday’s notebooks] on August 29th 1831  began the age of electricity.  Electricity is associated with the flow of electric charge, which is often equated with the flow of electrons and electrons are subatomic particles with a negative elementary charge and a mass that is approximately 1/1836 atomic mass units.  A moving electron, and it is difficult to find a stationary one, has wave-particle duality – that is, it simultaneously has the characteristics of a particle and a wave.  So, there is uncertainty about the nature of an electron and most of us find this concept difficult to handle.

An electron is both matter and energy.  It is a particle in its materialisation as matter but a wave in its incarnation as energy.  However, this is probably too much of a reductionist description of a systemic phenomenon.  Nevertheless let’s stay with it for a moment, because it might help elucidate why the method of measurement employed in experiments with electrons influences whether our measurements reflect the behaviour of a particle or a wave.  Perhaps when we design our experiments from an energy perspective then electrons oblige by behaving as waves of energy and when we design from a matter perspective then electrons materialise as particles.

All of this leads to a pair of questions about what is matter and what is energy?  But, these are enormous questions, and even the Nobel Laureate Richard Feynman said ‘in physics today, we have no knowledge of what energy is’, so I’m going to leave them unanswered.  I’ve probably already riled enough physicists with my simplistic discussion.

Note: an atomic mass unit is also known as a Dalton and is equivalent to 1.66×10-27kg

Source:

Hamilton, J., A life of discovery: Michael Faraday, giant of the scientific revolution. New York: Random House, 2002.

Pielou EC, The Energy of Nature [the epilogue], Chicago: The University of Chicago Press, 2001.

Popping balloons

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Balloons ready for popping

Balloons ripe for popping!

Each year in my thermodynamics class I have some fun popping balloons and talking about irreversibilities that occur in order to satisfy the second law of thermodynamics.  The popping balloon represents the unconstrained expansion of a gas and is one form of irreversibility.  Other irreversibilities, including friction and heat transfer, are discussed in the video clip on Entropy in our MOOC on Energy: Thermodynamics in Everyday Life which will rerun from October 3rd, 2016.

Last week I was in Florida at the Annual Conference of the Society for Experimental Mechanics (SEM) and Clive Siviour, in his JSA Young Investigator Lecture, used balloon popping to illustrate something completely different.  He was talking about the way high-speed photography allows us to see events that are invisible to the naked eye.  This is similar to the way a microscope reveals the form and structure of objects that are also invisible to the naked eye.  In other words, a high-speed camera allows us to observe events in the temporal domain and a microscope enables us to observe structure in the spatial domain.  Of course you can combine the two technologies together to observe the very small moving very fast, for instance blood flow in capillaries.

Clive’s lecture was on ‘Techniques for High Rate Properties of Polymers’ and of course balloons are polymers and experience high rates of deformation when popped.  He went on to talk about measuring properties of polymers and their application in objects as diverse as cycle helmets and mobile phones.

A big question for engineers

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galleyhead lightThe proportion of women graduating with engineering degrees in the UK and US has remained around a sixth for at least the last thirty years despite many campaigns to achieve gender equality.  One of my colleagues, Professor Elena Rodriguez-Falcon, writing in the New Statesmen asked whether it will take another world war to get more women into engineering.  I think that the sort of seismic shift in attitude caused by such events will be required.  Many in the engineering profession claim that problem-solving is a unifying skill, which is common to all branches of engineering, and yet we have been unable to solve the problem that our profession is one of the least gender diverse.  Does this mean that we have not really been trying to solve the problem, or that we are not the problem-solvers we claim to be?

Sources:

Landivar LC, Disparities in STEM employment by sex, race and Hispanic origin, US Census Bureau, September 2013

 

Entropy in poetry

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WIN_20140716_190901 (2)Few weeks ago I mentioned about reading undergraduate dissertations [see my post entitled ‘A Startling Result‘ on May 18th, 2016] and about a year ago I wrote about the low quality of prose produced by engineers [see my post entitled ‘Reader, Reader, Reader‘ on April 15th, 2015 ].  Coleridge described prose as words in the best order and poetry as the best words in the best order. So today I’d like to direct you to a poem entitled ‘Entropy‘ by Neil Rollinson from his anthology ‘Spanish Fly’.  Here are a few lines from it:

“I open the window, the sky is dark
and the house is also cooling, the garden,
the summer lawn, all of it finding an equilibrium.”

I came across it while reading an anthology called ‘A Quark for Mister Mark: 101 Poems about Science‘ edited by Maurice Riordan and Jon Turney.  I was dipping into it while enjoying a pint in our backyard after a personal battle with entropy: painting rusting railings in our yard.

I was reviewing ‘A Quark for Mister Mark’ as potential reading material for a module on Technical Writing as part of our new CPD programme on Advanced Technical Skills.