Emetophobia in the general population (Christie, 2004). Some experts believe that emetophobia may be linked to worries about lack of control. Many people try to control themselves and their environment in every possible way, but vomiting is difficult or impossible to control. There are many factors that can cause a legitimate case of emetophobia. Emetophobics are indeed severely mentally ill. Dr. Angela L. Davidson "et al". conducted an experiment where it was concluded through various surveys that people suffering from emetophobia are more likely to have an internal locus of control pertaining to their everyday life as well as health-related matters.
Periodic function were irrational, then the wave would not be periodic. Periodic function In mathematics, a periodic function is a function that repeats its values in regular intervals or periods. The most important examples are the trigonometric functions, which repeat over intervals of 2"π" radians. Periodic functions are used throughout science to describe oscillations, waves, and other phenomena that exhibit periodicity. Any function that is not periodic is called aperiodic. A function is said to be periodic if, for some nonzero constant , we have for all values of in the domain. A nonzero constant for which this is the case is