eye magnetic field sensitivity

Hi all,

Just a (crazy!) idea: when a rod/cone is energized by light hitting it
in the eye, this will generate an electric current through the rod, and
effectively make it a small electromagnet for a short time, which could
allow it to be sensitive to external magnetic fields.

cheers,
Jamie

 

Nerve stimulus is an electro-chemical interaction. There is no mag
field that is of any significance. The photon response the rods and
cones create is electro-chemical as well, and is very, VERY small.
Birds do not geo-locate with their eyes, there is a different, directly
brain connected region where that takes place.

There is more energy in the nerve axons repeating the data on the way
to the brain region it ends up in (visual cortex) than there is in the
original reception at the retinas.

 

There are "epic" photos for years on the internet of things that got too
close to the MRI.

 

Most people just notice the noise from the associated air conditioning.

Big degaussing coils and air cored mass spectrometer magnets are about
the most rapid dB/dT you find in common lab experience. I trashed quite
a few magnetic stripe bank cards when I worked with fast sweep high
power magnets. Never noticed any interesting sensations at all being
near them.

Some of the big hunky supply cables would visibly twitch as the current
sweep occurred. I always wondered just how long it would be before the
copper work hardens and snaps!

 

I mentally designed a circuit while it was happening. It sure helped to
pass the time.

 

The Alcoa aluminum plant on the Mississippi River between Iowa and ?
Illinois uses electric power for their smelting [for better thermal
control]. They built there and planned on having underground wiring
from the nearby adjacent power production facility, but could NEVER
get the leaks, or something, resolved with the underground technique,
so went to HEAVY lines hanging overhead. Standing at the facility I
looked out and saw the hanging lines visibly twitching almost touching
each other. My host commented that that was a 'quiet' day. Often the
wires hit together with such force [evidently same potential just
parallel current] they crack together and sound like rifle shots. His
answer to my asking wasn't that hard on the wires was, yes, they wear
out about one a year and have to be replaced.

 

pray the super conducting magnet doesn't quench abruptly.

 

other than the risk of asphyxiation from the boiling helium if it
doesn't get vented to the outside is it really that violent?

I mean it might ruin the magnet and if not it takes weeks to adjust
after restarting but its not like it is going to explode


-Lasse

 

There are a few examples of MRI quenches on YouTube. I can't look at them
because my laptop is sick but type "MRI Quench" on the search line.

It makes a lot of noise.