Volcanoes
The earth's surface is composed of big slabs of rock called plates. Volcanoes are form...
Polygraphs are often referred to as "lie detectors." However, this nickname is a bit misleading. Polygraphs do not directly identify lies. They track a subject's heart rate, breathing rate, and perspiration levels. Changes in these measurements often occur when a person tells a lie. It is up to the examiner to determine whether the information collected signifies an action of deceit. One difficulty in using a polygraph to detect lies is that any type of stress can lead to changes in our basic bodily functions. However, polygraph operators are well-trained and can usually identify which metabolic changes are results of stress not associated with acts of deception. For instance, for many people, being hooked up to a polygraph would be an unusual experience. This, in itself, might cause a certain level of change in heart rate, breathing rate, or perspiration levels. Examiners factor this in when evaluating a subject's metabolic reactions during questioning.
The earth's surface is composed of big slabs of rock called plates. Volcanoes are form...
On some dark nights in certain parts of the world, an amazing green glow appears on the ho...
Scientists have spent many years trying to figure out earthquakes. Massive slabs of rock, ...