Work

One of the first things I noticed when going through possible angles of approach to this topic is the sheer amount of nouns and verbs linked to Work. Although oddly enough, in the thesauruses and dictionaries I was checking very few mentioned a very real and defined version of Work. And as I vaguely remember questions about this in exams years ago it was a good chance to work out if I could still understand any of them now.

I’m talking about how to measure work. In the International System of Units (SI) then one joule is equal to the amount of work or energy done when a force of one newton displaces a body through a distance of one metre in the direction of that force. For example: lifting an apple one metre takes 1 joule of work or energy.

It is also the energy dissipated as heat when an electric current of one ampere passes through a resistance of one ohm for one second. It is named after the English physicist James Prescott Joule (1818–1889).

J P Joule

James Prescott Joule was born in Salford, he was the son of a renowned local brewer and grew up fascinated by all things scientific. He became particularly interested in electricity and was fortunate enough to be tutored by John Dalton, one of the leading chemists of the day. This expert tutelage, combined with Joule's personal obsession as well as access to some specialised beer-making equipment would ultimately lead to one of the most ground-breaking (and at the time, controversial) discoveries in the history of science: that heat is a form of energy.

In 1841 he discovered what became known as Joule's First Law. This defined the relationship between the amount of heat produced and the current flowing through a conductor. At this time things seemed to be going well, he was still an amateur scientist but had been accepted as a member of the London Electrical Society. He decided to look into the wider question of how much work can be extracted from a given source and soon found that the scientific establishment was strongly opposed to his ideas.

In 1843 Joule presented his results to a meeting of the British Association for the Advancement of Science, in Cambridge, but contemporary anecdotes claim that he was met by a stony silence. Undeterred, he continued his experiments. In 1844, believing he had compelling evidence, he submitted his paper to the most prestigious scientific group of all, the Royal Society… who refused to publish his work.

One reason was that Joule said he could measure temperatures to within 1/200 of a degree Fahrenheit, something that was simply unthinkable with the majority of scientific equipment available at the time. However, Joule had two advantages. One was his background as a brewer, which meant he had ways to measure much more precisely, as the finely tuned measurement of temperatures is critical to the brewing process. The other was John Benjamin Dancer, an exceptionally talented instrument-maker who created custom equipment for him.

instrument made by J B Dancer

In 1847 Joule once again presented his ideas, this time to the British Association at Oxford, which was attended by both Faraday and Kelvin. Eventually his ideas would become the cornerstone of one of the most fundamental scientific laws ever discovered, the First Law of Thermodynamics. In 1850, he was made a fellow of the Royal Society, in 1852 he was awarded the Royal Medal, and in 1872 he was named President of the British Association for the Advancement of Science, the same group that had rejected his ideas back in 1843.

Mario Petrucci is a poet, educator and broadcaster. He was born in Lambeth, London and trained as a physicist at Selwyn College in the University of Cambridge and later completed a PhD in vacuum crystal growth at University College London. He is also an ecologist, having a BA in Environmental Science from Middlesex University. Petrucci was the first poet to be resident at the Imperial War Museum and with BBC Radio 3.

Orders of Magnitude

One hundred thousand trillion joules
to turn an ice cap into mush
One hundred thousand billion joules
to erase a major Eastern city
A hundred thousand million joules
to run a car to death
One hundred million of the same
for Fire Brigades to reach the kitten
Ten million just to keep
December from cold feet
A hundred thousand joules for a mug
of tea – A hundred joules
for a second’s worth of War and Peace
Ten to raise a hand – to lift
an average apple to the lips
A single joule to shout the command
Half a joule to pull the trigger
Just one tenth to push the button
Almost zero to have the thought.

Mario Petrucci, from Flowers of Sulphur, Enitharmon, 2007

Thanks for reading, Terry Q.