An Engineer In Wonderland – A day in the Science Museum

exterior-of-museum-jpg.jpgI never tire of the Science Museum in London.

I can tramp the halls for hours without finding anything too dry to be of interest.

And I have spent a very long time in front of a cabinet in the locksmithing gallery getting more and more frustrated at failing to fathom one – or, to be honest, any – of the mechanisms behind the glass.

But this time I had a whole new experience there: Fun.


It turns out that all you need to do to have a giggle is take some children with you.


Because then you don’t feel such a fraud when you go into the all-hands-on Launchpad zone to play with the stuff in there.


And there is some amazing stuff.


For example, there is a magnet that is free to move in a gap between two slabs of copper.


inductioncrop.jpgThe amazing bit is that the magnet takes more than a second to fall 20mm through free space.

I realise it is all induction, and I also know that bits of superconductor happily float over magnets, but it never occurred to me that copper was conductive enough to visibly slow the fall of a magnet. Particularly almost to a standstill.









I am still a little puzzled why the copper slabs are joined at one end – anyone know?


And take a look at this video – which plays on a continuous loop in Launchpad.

It was made for the Museum to show children examples of energy transfer by Engineered Arts in Cornwall.


And I had an uncontrollable urge to make a bridge out of blocks

and an arch



and… there was still enough time to go and see the first prototype of the Clock of the Long Now, the Merlin engine I seem always to gravitate to, and the Foucault Pendulum.


This last thing is a very long pendulum that – in ways that I also cannot fathom – demonstrates that the earth rotates.

I tried to work out how oscillation in the pendulum is maintained without corrupting its direction of oscillation and came up with a coaxial electromagnet mechanism under the mass.

If the link above is to believed, this turns out to be the way most people do it.

But it appears the Science Museum – care of The Cavendish labs (they really did bring in the big guns then) – has come up with a completely different drive mechanism.


It was indeed a great day out.


Even the children enjoyed it.





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  1. 'Alice'
    May 11, 2009 10:13

    I did notice that the children’s exhibits had the allen-bolts-and-steel look that I normally associate with experimental pressure vessels.
    Maybe kid-proofing rather than electron flow explains the huge metal link between the slabs of copper on the floating magnet demo.

  2. Peter
    May 07, 2009 13:37

    Having visit this and other science parks over the years, I have come to the conclusion that there should be four grades of durability for switches:
    Domestic, industrial, military, childrens’ science park.

  3. Dubularity
    April 06, 2009 19:01

    Magnet/Copper – Isn’t it to do with Eddy Currents?

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