Misconceptions

in Misconceptions

Fallacious yet widespread and documented beliefs courtesy of Wikipedia.
A person who is drowning does not always wave and call for help. In the final stages, raising the arms and vocalising are even usually impossible due to the instinctive drowning response. The technical term for the situation where a drowning person is capable of waving and calling for help is aquatic distress.

in Misconceptions

Fallacious yet widespread and documented beliefs courtesy of Wikipedia.
Contrary to a widespread perception, the real number 0.999...—where the decimal point is followed by an infinite sequence of nines—is exactly equal to 1 by definition. They are two different ways of writing the same real number. A 2009 study by Weller et al. states that "Tall and Schwarzenberger (1978) asked first year university mathematics students whether 0.999... is equal to 1. The majority of the students thought that 0.999... is less than 1." Weller et al. go on to describe their own controlled experiment, performed "during the 2005 fall semester at a major research university in the southern United States. Pre-service elementary and middle school teachers from all five sections of a sophomore-level mathematics content course on number and operation participated in the study." The results are striking: "On the question of whether .999...=1, 72% of the control group and 83% of the experimental group expressed their view that .999... is not equal to 1."

in Misconceptions

Fallacious yet widespread and documented beliefs courtesy of Wikipedia.
The Coriolis effect does not determine the direction that water rotates in a bathtub drain or a flushing toilet. The Coriolis effect induced by the Earth's rotation becomes significant and noticeable only at large scales, such as in weather systems or oceanic currents. In addition, most toilets inject water into the bowl at an angle, causing a spin too fast to be significantly affected by the Coriolis effect.

in Misconceptions

Fallacious yet widespread and documented beliefs courtesy of Wikipedia.
Gyroscopic forces are not required for a rider to balance a bicycle. Although gyroscopic forces are a factor, the stability of a bicycle is determined primarily by inertia, steering geometry, and the rider's ability to counteract tilting by steering.

in Misconceptions

Fallacious yet widespread and documented beliefs courtesy of Wikipedia.
Humans have more than five senses. Although definitions vary, the actual number ranges from 9 to more than 20. In addition to sight, smell, taste, touch, and hearing, which were the senses identified by Aristotle, humans can sense balance and acceleration (equilibrioception), pain (nociception), body and limb position (proprioception or kinesthetic sense), and relative temperature (thermoception). Other senses sometimes identified are the sense of time, itching, pressure, hunger, thirst, fullness of the stomach, need to urinate, need to defecate, and blood carbon dioxide levels.

in Misconceptions

Fallacious yet widespread and documented beliefs courtesy of Wikipedia.
Shaving does not cause terminal hair to grow back thicker or coarser or darker. This belief is because hair that has never been cut has a tapered end, whereas, after cutting, there is no taper. Thus, it appears thicker, and feels coarser due to the sharper, unworn edges. The fact that shorter hairs are "harder" (less flexible) than longer hairs also contributes to this effect. Hair can also appear darker after it grows back because hair that has never been cut is often lighter due to sun exposure.

in Misconceptions

Fallacious yet widespread and documented beliefs courtesy of Wikipedia.
Hair and fingernails do not continue to grow after a person dies. Rather, the skin dries and shrinks away from the bases of hairs and nails, giving the appearance of growth.

in Misconceptions

Fallacious yet widespread and documented beliefs courtesy of Wikipedia.
Hair care products cannot as such "repair" split ends and damaged hair. They can, however, prevent damage from occurring in the first place, smooth down the cuticle in a glue-like fashion so that it appears repaired and generally make hair appear in better condition.

in Misconceptions

Fallacious yet widespread and documented beliefs courtesy of Wikipedia.
Eight glasses of water a day are not necessary to maintain health. Consuming things that contain water such as juice, tea, milk, fruits and vegetables also keeps a person hydrated.

in Misconceptions

Fallacious yet widespread and documented beliefs courtesy of Wikipedia.
Sugar does not cause hyperactivity in children. Double-blind trials have shown no difference in behavior between children given sugar-full or sugar-free diets, even in studies specifically looking at children with attention-deficit/hyperactivity disorder or those considered sensitive to sugar. The difference in behaviour proved to be psychological.