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Back to Frequently Asked Astronomy and Physics Questions
How are surgical lasers different from the lasers that they use on
Star Trek?
Lasers, as you probably know, produce intense radiation using a specific
quantum mechanical mechanism ("Light Amplification by Stimulated Emission
of Radiation" --- LASER). Whether the laser is used for surgery or not,
the mechanism is the same. Larger lasers can produce more energy.
(Actually, I'm not sure the Star Trek characters are using "lasers" at all
--- I thought they called them "phasers", in which case I haven't the
slightest idea was 24th(?) century technology they're using!)
How can you change the colors of the lasers and is one color stronger
that the other?
The color doesn't matter much to the strength --- it's, for example,
the size (amount of
light emitting material that matters), and other attributes of the laser
that matter.
One can change the color by using different materials for generating the
light. A helium-neon laser generates the familiar red laser light, other
materials can generate green laser light, etc.
What are the primary ways physicians use lasers?
I'm not sure, but laser light can be pinpointed at specific small regions
that a knife either cannot reach, or that a knife can't do a fine enough
(small enough) job on. An example: a laser can be used through the lens of
the eye to treat problems on the eye's retina (however, I'm not sure of
the details of this, or any other procedure). I recently saw a TV news
report where a laser was being used to remove skin that had been damaged by
burns. The surgeon said the laser was more precise than a knife, and
resulted in less scarring after the patient healed.
How do you think lasers will be used in the year 2000?
That's not too far away. I don't think there will be any great changes by
then. However, surprises have a way of appearing without expectation!
What are some uses of Gamma Rays?
I don't know of any practical uses, although that doesn't mean there aren't
any. Scientific uses include observational
astronomy (there are sources of gamma rays in the Galaxy, and elsewhere),
physics (nuclei emit gamma rays telling of their nuclear structure, gamma
rays appear in accelerator experiments, etc.).
It's gamma rays that are used in radiation treatments of cancer.
What are some uses of Ultraviolet rays?
Besides the observation of UV in astronomy, UV is probably used in some
medical treatment of skin conditions. Of course, solar UV, while not "used" for
this purpose, does cause skin cancer when an individual is exposed to too
much of it. UV can be used to sterilize things (abundant UV kills
bacteria, and any other cells).
What are some uses of Infrared Radiation?
Infrared is also called heat rays. It is used to warm muscles, etc.,
during some treatments of medical conditions, or sports injuries, etc.
Are there any other main rays in the electromagnetic spectrum, that are
harmful besides UV rays, Infrared Radiaton, Gamma Rays, and X-rays?
All radiation can probably cause some problems, in high enough doses. Its
just that what consititutes "high enough" is different for each.
Microwaves can literally "cook" you! (That's what a microwave oven does!).
But you need a high intensity. Even visible light, if intense enough, can
blind you (even if your eyes are shut). But we don't normally encounter
such high levels of microwaves or visible light.
[Where can I] get some more information on Gamma Rays?
Try searching the internet for any pages that contain the works "gamma
rays", or other such words and phrases. A nice search engine to use is the
Webcrawler.
Just go to that site; the instructions for use a simple.
