Fiducial or fiduciary – that is the question!

Very quickly:

A fiducial marker (noun) or fiducial for short is an object used to indicate a measurement reference point either to indicate scale or an original position or to aid more precise measurement.

A fiduciary (noun) is a person who holds a position of trust between parties for legal or financial reasons. The word fiducial (adjective) in this context indicates the actions or activities of a fiduciary.

I can see the confusion these two terms might cause. But it’s not a confusion a scientist is likely to make because we learned our words proper-like. So this leads me to think that the legal team at the DfE drew up the plans for the AS and A Level physics*. For, lo and behold, in the DfE guidance for the AS and A Level physics – students must be aware how to: fiduciary_dfe

It’s ok, one thinks, the subject specialists at the exam boards will pick it up.

AQA spec:


OCR spec:


EdExcel spec:


WJEC spec:


So once again, the DfE blunders (due in part to their desire to over-specify every part of the curriculum) will come to shape the teaching of physics students up and down the country, and they won’t know what the correct word for a fiducial marker is.

Spotted by the excellent Carol Davenport @drdav on the Twitters who is as frustrated by DfE physics blunders as I am.

*It doesn’t really, it’s probably just an administrative mistake.

Transit of Venus

How far away is the sun?

To answer this simple question took a huge amount of cooperation in what was to be the first international scientific collaboration of its kind. Nowadays international scientific projects are commonplace, but in the 18th century it took a rallying call to observe an a rare astronomical event. This event had been predicted to occur in 1761 and again in 1769 and the scientific community was determined to take advantage of this prediction to collect data for a mathematical solution to find the distance to the sun first proposed over 50 years earlier.

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