School knowledge, which does not hurt to remember.
“And what is it to teach? All the same, because in life not useful!”. Probably, in the childhood every once asked myself this question, sitting on boring lessons. But there is a world of useless knowledge. A lot of “unnecessary” school information is very useful in adult life. For example, here is the 8 school tricks that don’t need to remember all.
These facts and skills many of us learned in school but probably forgot, barely leaving the school. It’s time to reveal the “halls of memory” and get out of them a bit old-new, but equally useful knowledge.
1. How to calculate the time remaining before sunset
Counting the hours and minutes until sunset.
When the sun leans towards the horizon, raise your palm horizontally in front of eyes. Make the disk of the sun “touched” the index finger. Now count the number of fingers from the sun to the horizon (you can substitute and a second hand, bottom). Each of them is about 15 minutes. For example, 4 fingers between the sun and the horizon is 1 hour before sunset. A very useful scout trick that is cool handy camping, fishing or when you want to impress a girl on a romantic date.
2. How to understand the moon increases or decreases
To distinguish between “growing” month of “aging”.
You need to mentally connect the corners of the Crescent vertical line. If the moon is like the letter “C”, then it decreases (you can remember like “C = Older”), and if the letter “R” – is growing.
3. To understand Roman numerals themselves are not worse than the ancient Romans
Cheat sheet for remembering Roman numerals.
Roman numerals for a modern person – a little easier cuneiform. To get my head around the basics of numbering will help the rule of thumb. Read and remember this strange phrase: “We Dарим Juicy Lимоны Enough Vсем IX”. The first letter of each word is a digit (in descending order): M = 1000, D = 500, C = 100, L = 50, X = 10, V = 5, I = 1. A good tip for living in MMXVIII.
4. To stop guessing, this month 30 or 31 days
To calculate the number of days in the month without a calendar.
You just heard about this trick in high school. Both hands in fists and start counting knuckles. Each bone and each trench is a month. We start, of course, since January. Knuckle = 31 days, and depression = 30. Oh yeah, how many days are in February?
5. How to multiply on your fingers
Multiplication table 6-9, which you can “spy” on the hand.
Multiplication table – a big hassle, especially when it exceeds 5. But if the failure in school knowledge keeps reminding me about it, you can always multiply numbers from 6 to 9 on his fingers. To do this, look closely at his hands, lowered them, palms down. Number each finger 6 to 10, starting with the little finger. Now, to multiply, for example, 8 to 7, connect the “eighth” finger of one hand with the “seven” of the other (as pictured). All the fingers that are on the bottom and the United dozens. In our case, the “5”. And fingers from the top of the unit and the number to multiply each other. In this example 2 x 3 =6. Total: 56.
6. Measure the length of small objects without line
Measure without a ruler.
Here, too, you can count “on the fingers”. Just remember that the distance between the tips of the thumb and index finger approximately 18 cm, and between the thumb and little finger is about 20. Of course, due to “personal settings” (ie, size) of each result will never be accurate to the millimeter. But at least some guess.
7. And measure the angle without a protractor
Angles without a protractor.
The protractor is the second of a compass item that every third consistently forgot to put in a bag and bring it to your geometry. Without having to get out. If you remember that the angle between the thumb and the little finger in the “normal spread” position = 90 degrees, between the little finger and ring = 30 degrees, little finger and middle = 45, and the pinky and index = 60.
8. To check if the battery is charged
“Dead” or “alive”?
Physics test for 7th grade: drop a battery from a small height, holding it vertically. Fell to one side exhausted. But if bounced, but kept an upright position – more work.
But this is just the beginning. As “berries” look at 8 of the most unusual items that examine students in different countries.