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.
A fuller version of the video can be seen on the Nature website
Bookmark with:
What are these?