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X-Ray your finger with stickytape! Answered

Scientists have discovered the cheapest source of potentially-useful X-rays.

Peeling sticky tape emits X-rays strong enough to scan a human finger, a remarkable experiment has shown.

US researchers used a motorised peeling machine to unwind a roll of Scotch tape at a rate of 3cm per second.

By placing their apparatus in a vacuum, they measured X-rays strong enough to X-ray a human digit, according to a report in Nature journal.

It is well known that unwinding sticky tape produces sparks of light that can be seen in the dark by the naked eye.

This phenomenon, known as "triboluminescence", is produced by the friction generated when two surfaces rub against each other.

The study, by Carlos Camara and Juan Escobar, of the University of California, Los Angeles, USA, provides evidence for the phenomenon, which was first observed more than 50 years ago.

BBC story, with video


Too bad it only works in a vacuum.

Wow, that's pretty incredible.

I saw this and forgot to post it, they weren't sure why it did that when I read the article... Instantly I assumed that the voltage must be over 50KV in the sparks, I know that makes X-rays in a vacuum... I wonder why they had decided to do it in the first place, maybe to see if it still worked in a vacuum but...

According to the full video on Nature, they first did it because they didn't believe the theorists who said it would happen.

Now they're taking about developing it into a useful medical tool, potentially for the developing nations, because it is a far cheaper device than the X-ray machines used by dentists.

You wrote:
>> According to the full video on Nature, they first did it because they didn't
>> believe the theorists who said it would happen.

Speaking as an experimentalist, that is always the best reason to do any experiment! We get points for making theorists look silly, and extra bonus points for making them look right ;-/

True :-)

(Thought experiments are so much cheaper, though, and the results are so much more elegant, being utterly devoid of annoying things like decimals, or units)

I would like to get some free time to do such things, see I often make wild and quite strange predictions as to the outcome of some stuff, they're not always wrong and they're not always right, however it's hard to tell how accurate they are in a non scientific environment.

It occured to me that a combination of capacitors and diodes could be used instead, a voltage multiplier like plasmana's with the HV output creating X-rays, once encased in insulating wax it'd be pretty rugged. I wonder how cheap ultrasound machines are, it occurs to me that a clever made one could have a wider range of applications.