Did the doctors remove the rod from Phineas Gage's skull?
Laura and Jim
The 3 feet 7 inch iron tamping rod was propelled (by the explosion) with such force that it drove it straight through his skull. There was no need to remove it.
Dear Dr. Bob,
I am very impressed with the effort you are putting to make this page more interesting. Please oblige me by answering this question, for it has kept me wondering for quite some time.
Gamma waves, radio waves, micro waves, X-rays, ultra-violet rays and infrared rays, all have different wavelengths, but do they have different speeds? If so, which one is the fastest?
Thanks,
DCH
The waves that you mention above are all part of the electromagnetic spectrum. The electromagnetic spectrum has no definite upper limit or lower limit. The following diagram shows where the various types of electromagnetic radiation fall from long wavelength (low frequency) to short wavelength (high frequency).
Power Microwaves Visible X-Rays
Radio Infrared Ultraviolet Gamma Rays
LONG WAVELENGTH -------------------- SHORT WAVELENGTH
(low frequency) (high frequency)
All forms of electromagnet radiation travel at the same speed in free space (a vacuum). This speed is referred to as c. Electromagnetic radiation travels at an amazing speed of 299,792,500 meters per second (approximately 186,000 miles per second) in free space.
Although there is agreement that all forms of electromagnet radiation travel at the same speed, interestingly there is not total agreement concerning whether the speed of light has remained constant over time. For more information on this interesting topic please refer to the question on this topic in Volume 1 of Q & A.
What are the smallest sharks and how much do they weigh and what are the largest sharks and how much do they weigh, also what sharks live in the Tampa bay or Gulf beach area in Florida? Thanks for the info.
Thanks,
Mikey
The dwarf shark is the smallest shark. It is only 6 inches (15 centimeters) long and weighs less than a pound (<.45 kilograms) . Another small species is the cookie-cutter shark which measures less than 19 inches (50 centimeters) in length.
On the other end of the spectrum, there is the largest of all sharks, the Whale Shark. This species can reach up to 50 feet (15 meters) in length and weigh more than 18 metric tons. Interestingly, the Whale Shark is strictly a filter feeder who strains plankton and small fish from the upper layers of water, in tropical and subtropical seas, by lying motionless beneath the water's surface.
Some common sharks in the Florida area include Nurse Sharks, Reef Sharks, and the common Dogfish.
Dear Dr. Bob,
I am trying to think of a good science fair project about electromagnets. My teacher says I have to measure something and make up a graph. Do you have any experiments with one variable about electromagnets for an eighth grader?
Thanks,
Josh
Electromagnets are interesting and fun to make. I will give you some hints for an interesting project (as part of your assignment you can figure out exactly how to do the experiment).
One property of an electromagnet that you can easily change is the strength of the magnet. It can be changed by increasing the number of wraps of wire or by changing the battery voltage. Can you think of a way to measure how strong different electromagnets are?
I hope that these hints will get you started on a great experiment!
I found the "Hole in the Head" article interesting, especially since it addressed head injuries, vis a vis swelling of the brain, etc. My father has recently suffered a cerebral hemorrhage, according to CT scans and subsequent surgical removal, affecting the right parietal lobe. Since all of this has only transpired in the last week, I realize we have a long way to go before getting any concrete prognosis. Still, I am interested in finding out what the parietal lobe controls, since he has not only been apparently paralyzed on the left, but is having trouble emerging to consciousness. He seems rather desperate to communicate something to us, yet whenever we're with him he becomes agitated and his blood pressure soars (I saw one reading top 250 yesterday - frightening).
I am of course communicating with the neurosurgeon about the specifics of this case, so I'm not asking for medical advice per se. But I wonder what some of the POSSIBLE explanations for this discouraging turn of events (namely, no particular movement in the direction of improvement or decline) could be.
Dad's a "young" age 78, physically very strong, has hypertension and has previously, about a year ago, experienced a "TIA" stroke. He's stubborn as heck. We can't figure out if he wants to fight or give up. Can his mental faculties be impaired after such an event, or is he simply unable to communicate? The hemorrhage was large, clotted and remained for about 3 days, and did exert sufficient pressure as to rearrange his brain. However, CT scans since surgery demonstrate this marvelously elastic tissue (his brain) has pretty much returned to normal. At least the shape and location of all the parts look normal again.
Any insights would be helpful. It is, of course, the doctor's job to help us remain hopeful. I am looking for cold scientific fact. I am unable to turn up anything specific in numerous search engines on an injury of this size. There has been, in fact, no definitive diagnosis (stroke? or hemorrhage from some other injury? or...?).
Thank you,
Denise
I am sorry to hear about your father and I wish the best concerning his recovery. As stated in your note, all medical advice concerning his condition should come from his neurosurgeon and other medical experts associated with his case. As such, my response will be limited only to the "cold scientific facts" concerning the function of the parietal lobe.
The parietal lobes occur in the cerebral hemispheres. They are responsible for integrating sensory stimuli (e.g. touch) that allows the recognition and recall of form, texture, and weight. The parietal lobes process these sensations to create self-awareness of the world. Other parts of the parietal lobe are responsible for transacting mathematical functions and recognizing language and words.
As a result, some of the following problems may occur as a result of damage to this area of the brain:
Please note that conditions that I have mentioned MAY occur with injuries to the parietal lobes. I hope that in your father's case there is full recovery and you experience none of these. Best of luck.
Dear Dr. Bob,
At school we were talking about eclipses and it was mentioned that the ancient Chinese had a belief as to what caused solar eclipses but it was not explained. Could you please explain what this belief was.
from another Bob (Robert E., age 11)
Long ago, there were many beliefs concerning the heavens that today we know are not true. Regarding your question, the Chinese people believed that a dragon swallowed the sun when an eclipse of the sun occurred. Some other interesting ancient beliefs were:
As a result of the advances we have made in science, we know now that these things are not true.
Is the Top Quark which was discovered at the Fermi Lab the same thing as the Higgs particle? If not, what is the difference? If they are not the same, have they found the Higgs particle? Thanks Dr. Bob. You are the goods.
Sean
The Top Quark and the theoretical Higgs particle are not the same. Quarks are one of the basic constituents that make up protons, neutrons, and mesons. Protons, neutrons and electrons are the basic particles that make up atoms and hence all the matter that surrounds us. There are 6 varieties of quarks which include the up, down, strange, charm, bottom, and top quark.
The Higgs particle, on the other hand, is a particle that is theoretically responsible for giving mass to other particles (including Quarks). The Higgs particle has yet to be found.
Dear Dr. Bob,
Do male kangaroos have pouches?
Just wondering,
Amy
Male kangaroos do not have pouches. Female kangaroos, of course, have pouches where the teats and mammary glands are located and the young are raised. A baby kangaroo climbs into its mothers pouch about 1 to 5 minutes after birth.
What is the difference between centripetal force and centrifugal force? When/where do you use centrifugal force?
Thanks for your help.
Stephen
To understand the difference between centripetal force and centrifugal force we must consider uniform circular motion (an object moving in a circle). Centripetal force acts on an object and is directed TOWARD the center of the circle. For example consider swinging an object around on the end of a rope. As long as the rope is held securely (centripetal force) the object on the end of the rope will continue to travel in a circular path. When the rope is released (no centripetal force) the object will fly off on a tangent.
Centrifugal force, on the other hand, is directed AWAY from the center by the rotating object. Centrifugal force is therefore a "fleeing from the center" force. Centripetal force and centrifugal force are an action-reaction pair.
What is hair for?
Thanks,
Paul
Most mammals have three different kinds of hairs that each serve a different purpose. If you have ever looked closely at a large dog, like a Newfoundland, you will notice two types of hair that make up the coat. The outer course hairs are called "guard hairs". These hairs protect the rest of the coat from abrasion and also provide protection from moisture. They also provide coloration to the animal. The "underfur" is generally thick, fine hair that acts as an insulator for the animal.
The third type of hair is called the "vibrissa." These hairs are stiff and elongated and their primary function is tactile sensation. These hairs can be found around the lips, nostrils, eyes, and cheeks. A dog's whiskers are a perfect example of these tactile hairs.
I HAVE A DAUGHTER THAT IS 11 YEARS OLD AND IN 6TH GRADE. FOR A HOMEWORK ASSIGNMENT SHE HAS TO BRING IN A DISPLAY OF AN ATOM. DO YOU HAVE ANY SUGGESTIONS?
EVETTE
I am not sure exactly what type of display your daughter has to make but I think the simplest would be a poster showing diagrams of different atoms. A simple approach would be to draw a circle that represents the nucleus. Inside the nucleus are neutrons and protons. Orbiting the nucleus are electrons. This can be drawn very much like the earth (an electron) circling the sun (the nucleus).
She might show a hydrogen atom (the simplest atom) that contains 1 proton in the nucleus and 1 electron circling the nucleus. A more complicated atom would be nitrogen with 7 protons and 7 neutrons in the nucleus and 7 electrons circling the nucleus. Each element has a different combination of protons, neutrons and electrons.
I think that this might be an appropriate level of depth at the 6th grade level. Please note, however, that this representation is very simplified. When your daughter takes chemistry in college, she will learn some additional things about atoms including: 1) electrons in an atom occupy orbits of different energy levels 2) orbitals are referred to as s, p, d, and f orbitals and each have a unique shape, 3) electrons circling an atom are best visualized as electron "clouds" showing areas of high and low probability of finding an electron.
Good luck!
Hi Dr. Bob,
How was the Internet formed?
Thanks,
Carlo
The Internet was born on January 2, 1969. A team of scientists, supported by the Advanced Research Projects Agency (part of the Department of Defense of the United States Government), were conducting research on packet-switched networks. This work focused on computer networks that break down information into little "packets" which move through various networks until they reach their destination. This system was very important to the US government because it would assure that military communication would continue in the event of a war. If a particular communication line was severed, the information would simply take a different route.
Researchers doing this work found that the network was a great way to communicate. In 1983 two separate networks were formed, a military network called MILNET and a civilian network called ARPANET. It was also possible to share information between these networks. This interconnection was know as the Internet.
The next major advance came in 1986 when the National Science Foundation created the Internet "backbone" with five supercomputer networks. These backbones were information superhighways. As time moved on, many other computer networks connected to the Internet with the final result being the immense worldwide network that we have today.
What is the noise that locusts make. Are they mating? Do they really only visit every so often? We really enjoyed your site...
bbenke at AOL
Locust is a name used to describe two different kinds of insects; the short-horned grasshopper and the cicada. The sounds that you refer to are probable those that arise from the short-horned grasshopper and they are made by rubbing one part of the body against another part (e.g. the hind legs against the wings). This sound is indeed used to attract a mate.
From time to time, huge swarms of locusts appear in Far Eastern countries and in the western United States. These huge swarms may contain 100,000,000 to 1,000,000,000 insects. When they occupy an area they do vast amounts of damage to trees and crops.