Eero Pelkonen, 7
The usual the weight of a concrete apartment building is roughly estimated to be on average 1,000–1,200 kilograms per square meter.
That is, if the house is 15 meters wide and 28 meters long, the weight will be about 500,000 kilograms, or 500 tons per floor. In this case, a six-story house weighs about three thousand tons.
The building itself then weighs around 900–1,000 kilograms per square meter. Movable property, house occupants, etc. may weigh up to 200 kilograms per square meter. For the sake of comparison, let’s say that one compact car weighs approximately one ton.
If the apartment building is an old brick building, it weighs more on average than concrete apartment buildings.
For example, the average weight of the popular Art Nouveau apartment buildings in Katajanokka, Helsinki can be about 1.5 times compared to a concrete apartment building. New wooden apartment buildings, on the other hand, weigh less than concrete buildings.
The average weight per residential floor of a wooden detached house is about half that of a precast concrete house. If the width of a wooden house is 7.5 meters and the length is 14 meters, the weight of the house is about 60 tons.
In Finland, a 1–2 meter thick layer of crushed stone is usually brought to the construction site, which can weigh around 400 tons under a house that already weighs 60 tons.
Large buildings are a different matter. The Burj Khalifa skyscraper, located in Dubai, United Arab Emirates, is about 800 meters high and weighs about 500,000 tons. The Giza pyramid in Egypt is even more than ten times heavier.
Tim Länsivaara
professor of foundation engineering
University of Tampere
Anssi Laaksonen
professor of concrete structures
University of Tampere
Why are people’s shadows bigger than people really are?
Otso Hiekkataipale, 12
Human the shadow is the area on the ground where the light of the sun or other light source cannot reach. This happens because the person is in front of the light.
When the sun is low, it can easily be hidden from view. The lower it is, the longer the person’s shadow is. As the sun climbs higher in the sky, the shadow is shorter.
The shadow becomes longer than the person if the sun is less than 45 degrees in the sky, when the person is standing more or less flat.
This is almost always the case in Finland, but at Midsummer, the shadow is shorter everywhere except the northernmost part of the country.
Further south in Finland, the sun climbs higher in the sky. For example, in Spain, at midday in the summer, the sun is so high that a person’s shadow is clearly smaller than the person himself.
You can also try changing the length of the shadow yourself in the dark under the light of a street lamp. When standing under a street lamp, the shadow is small. When you walk further from the lamp, the shadow gets longer.
Tiera Laitinen
investigator
weather Institute
Who cuts the umbilical cord of wild mammals such as bears?
Emilia Winqvist, 12
Most of them mammals have an umbilical cord. The function of the umbilical cord is to connect the placenta, which is built in the wall of the uterus of a female mammal, to the fetus growing in the womb. In this case, the fetus receives nutrition and oxygen and is able to remove unnecessary waste materials.
Sedentary mammals include marsupials, such as kangaroos and wombats, and platypus, such as the platypus. That’s why they don’t even have an umbilical cord.
When the chick is born, the placenta stops working. The blood vessels in the umbilical cord shrink. The chick takes its first breaths of air into its lungs, when the blood begins to circulate between the heart, lungs and tissues.
In many mammals, the umbilical cord breaks on its own when the mother or the young move after birth. For example, when a giraffe gives birth, the baby falls from a height of more than one and a half meters to the ground, and the fall cuts the umbilical cord.
Again, many predators, such as bears, act so that the female cuts the umbilical cord by biting it across after giving birth.
Female beasts also often eat the placenta that comes out after the chick. The nutrients and hormones it contains are helpful for them when milk secretion begins.
Juha Valste
evolutionary biologist and nonfiction writer
Where does the saying “comes out of the ears” come from?
Heidi Tukia, 11
Sayings and figures of speech are often borrowed from one language to another. The Swedish expression “står ut genom öronen” is similar to the Finnish saying “it comes out of the ears”, which literally means “it comes out of the ears”. So the Finnish expression probably originates from Sweden.
That saying can be used in Finland as well as in Sweden for all kinds of boredom.
It probably started with the idea of eating. When you eat your stomach so full that you don’t want to fit any more.
This is indicated by the fact that the same thing can be said that “I am filled to the brim with this”. That expression can also be found in both Finland and Sweden. In Sweden it is “har det upp i halsen”.
The expressions in question are humorous. You really can’t eat so much that it comes out of your ears or is full up to your throat.
In England, on the other hand, getting enough is often indicated by the expression “fed up”, which literally means “fed up”. Also, the Finnish verb “saturation” has the same base as “kyläinen”, which refers to a full stomach.
Ulla-Maija Forsberg
professor of Finno-Ugric languages
university of Helsinki
Send the question, the questioner’s full name and age to [email protected]. The column is edited by Touko Kauppinen and Juha Merimaa.
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