column questions and answer
What is the size of the largest butterfly?
Tizaniya Agrippina (Thysania agrippina) - The world's largest butterfly stretch of wings, which reaches up to 30.5 cm, which is larger than that of a number of birds. This butterfly, which grows to a truly impressive size, belongs to the family of moths and Scoop inhabits pristine rainforests of South America.
A very large wing area, reaching up to 263.2 cm ² with a maximum span of up to 28 cm, belongs to another moth of the family Pavlinoglazok - Kostsinostsere Hercules (Coscinocera hercules), from Australia and New Guinea. But these gigantic reach only a few females.
Which area in Paris?
In view of Boulogne and Vincennes woods, nahodyaschixsya to vostoky and west of the city, respectively, the area of the city is 105 km ² and about 87 km ² with no parks.
Dwells there in Loch Ness Nessie?
Probably not. The main argument of the skeptics is the undeniable fact that the amount of biomass in the lake is not enough to sustain life being kind of space assigned to Loch Ness monster. Despite the enormous size and plenty of water (here brought by seven rivers), the Loch Ness has a poor flora and fauna. During studies of Loch Ness Project, identified dozens of species of living creatures. However, sound scan showed that the lake is only 20 tons of biomass, which is sufficient to sustain the life of a creature weighing no more than 2 tons.
Supporters of the reality of "Nessie" link to the old legend that on the bottom there is a network of caves and tunnels that allow you to float away into the sea monster and go back. However, surveys of bottom and banks suggest that the existence of these tunnels are unlikely.
Dogs see in the dark?
Dogs see in the dark better than humans, but not as good as a cat. Measurements of scientists, dogs perceive objects in the illumination up to six times lower than that which is necessary for orientation in space, man. In addition, the dogs quickly adapt to the dim lighting. This is explained by the fact that the dogs in the center of the retina is more light-sensitive cells - rods that work better in the dark than the color-cones. Lens of the eye is closer to the retina, which makes the image more vivid.
But the biggest advantage of the dog in front of a person's vision - the presence of tapetum (tapetum). Located behind the retina, the layer acts as a mirror. This structure reflects the light received by the eye, re-sending it to the retina. Tapetum is responsible also for the dog eye glow in the dark.
How many people per year die due to medical errors?
In Russia, the official statistics of deadly medical errors no leads. According to estimates of public organization "League for the Protection of patients' medical errors and trash kill each year of life 50 thousand people. It is unlikely that doctors with such terrible figures agree. However, physicians themselves recognize that every third diagnosis - wrong. The announcement was made three years ago at the first national congress of therapists. Doctors explain such frightening statistics shortages generated by the meager wages, and congestion of staff.
How vibration creates a mobile phone?
As the vibrator used DC motor. Motors powered by DC can convert electrical energy, such as batteries, to mechanical vibrations. This movement can be used to rotate the wheels robot, for example, or to create vibrations of the same phone. In fact, DC motor can be used anywhere you want to receive the mechanical motion.
Who and when was invented the guitar?
The earliest surviving evidence of stringed instruments with a resonating body and neck, the ancestors of modern guitar, refer to the III millennium BC. Oe. Images kinnora (Sumerian-Babylonian stringed instrument, mentioned in the biblical legends) were found on clay bas-reliefs in archaeological excavations in Mesopotamia. In ancient Egypt and India were also known similar tools: Nabla, Nefer, zither in Egypt, wine, and sitar in India. In ancient Greece and Rome, was a popular tool cittern.
The predecessors of the guitar had a long rounded hollow soundbox and long neck stretched with strings on it. The housings are made whole - from dried gourds, turtle shell, or hollowed out piece of wood. In the III-IV centuries AD. Oe. in China there are tools Juan (or yuan) and yuetsin whose wooden hull was assembled from the upper and lower decks and connecting their shells. In Europe, this led to the emergence of Latin and Moorish guitars around the VI century. Later, at XV - XVI centuries is a tool vihuela, and to influence the design of the modern guitar.
Why his eyes change color?
First, our eyes adjust to the color of our clothes and lighting - the pigment that distinguishes the retina has different color shades.
Second, eye color can hang on the weather, the mood (mostly - stress) on a number of ultra-violet rays falls on the retina.
Third, the majority of people's eyes change color to a lighter with age. This is especially noticeable after 40 years.