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- How to round a number to the tenths
Math allows you to turn the numbers in approximate values. It's not always at home person, have a "tail" hundredths, thousandths, etc. shares. From the correctness of a result of rounding often depends on interpersonal outcomes, as in the relationship between the cashier and the customer when paying at the checkout. - How to determine the charge of the ion
In some atoms and molecules can either acquire or lose electrons. In this case, the formed ion. Thus, the ion is a monatomic or polyatomic charged particles. Obviously, the most important characteristic of an ion is its charge. - How to divide a segment into equal parts
When solving problems in geometry it is sometimes necessary to divide a segment of straight line into equal parts. By the way, this problem can arise in ordinary everyday practice, if, for example, is required to drive nails in the wall at equal distance from each other. There are several ways to solve this problem that do not require significant calculations. - How to find the side of a square, knowing its area
Square - flat-regular quadrilateral or an equilateral rectangle. So right that all of its characteristics are equal to each other: hand, diagonal, corners. Because of the equality of sides the formula for calculating area of a square is modified, which is absolutely not complicated tasks. - How to find the hypotenuse knowing the lengths of the legs
Right triangle – a flat figure, which one of the angles is straight, that is, is ninety degrees. The sides of the triangle have names: the hypotenuse and two sides. The hypotenuse is the side of the triangle opposite the right angle, and the legs, respectively, adjacent to it. Basic math game parties is conducted through the Pythagorean theorem, which States that the sum of the squares of the legs equals the square of the hypotenuse. Think that sounds complicated, but actually everything is much simpler. - How to make lye
For the preparation of some perfumes (e.g. soap) will certainly require lye. The soap itself is the result of saponification of vegetable or animal fats with alkaline solution. Unlike liquid soap, in the manufacture of which uses potassium hydroxide, for making bar soap requires sodium hydroxide (caustic soda). Is it possible to prepare such alkali at home? - How to find the mass of air
Air is a natural mixture of gases consisting mostly of nitrogen and oxygen. The mass of air per unit volume may vary if changing the proportions of its components and also when the temperature changes. The mass of air can be found, knowing the volume that it occupies, or the amount of substance (number of particles). - How to determine the diameter of a circle
Circle - a closed curve whose points are equidistant from its center. The main characteristics of the circle are radius and diameterrelated to each other both visually and arithmetically. - How to calculate logarithm on a calculator
Logarithm number b for the base a is defined as a measure of the degree to which it is necessary to build a base a, to obtain the number b. As a rule, modern calculators allow you to calculate logarithms base 10 and e, that is, decimal (log) and natural (ln) logarithms , respectively. - How to find the surface area of a rectangular parallelepiped
This is called a rectangular parallelepiped, all six faces of which are rectangles. The formula for calculating its surface area is very simple: S = 2(ab + bc + ac), where a, b and c – the lengths of the edges. - How to find the radius of the chord
A chord is a segment connecting two points of the circle. Let the length of the chord is known. Then, if is also known the angle between the radiiconducted to the ends of the chord, then you can find the radius of the circle. - How to determine the charge of the atom
The charge of the atom, along with its quantum numbers, is one of the most important numerical characteristics of the atom. Knowledge of the charge of the atom is necessary for the decision of various problems of electrostatics, electrodynamics, atomic and nuclear physics. - How to distinguish a verbal adjective from the communion
In linguistic literature there is a different approach to the sacrament. It is regarded either as a form of the verb, either as a separate part of speech, or include an adjective. But according to tradition, the sacrament is called a special form of the verb. Verbal adjective formal similar to the sacrament. But they need to differentiate, because it affects the spelling and accuracy of morphological analysis. - How to do it yourself embossed on the leather
Leather is a great material for making a variety of useful items. Watch straps, bookmarks for books, cases for keys, or the covers of the notebooks, made of leather, can be a wonderful gift. This souvenir can be supplemented with beautiful embossing. - How to prepare sodium chloride
For such a complex chemical called "chloride of sodium" hides in plain salt. Like any other substance it can be both dangerous and useful. The main thing is to apply it. - How to find the angle knowing the cosine
In addition to direct trigonometric functions sine and cosine, there are and return them to the arc sine and arccosine. They can be used to calculate the angles using the known values of the direct functions. There are several variants of practical implementation of such calculations. - How to clean kerosene
Kerosene is a product of processing of heavy oil used in households as fuel. Subsequently, kerosene was used as fuel for rocket engines. In our days there are persistent rumors that in addition to the use as fuel, kerosene may be applied in the treatment of certain diseases. Let's leave the discussion of the question of the reasonableness of the use of kerosene for medicinal purposes traditional healers; let's try to figure out how to clean kerosene in the home. - How to determine the density of water
Water is one of the key compounds on earth. Many scientists believe that in her life began. It is unique. For example, this is the only fluid that is compressed upon lowering temperature, and this is a very important feature. Some of its properties are anomalous. Values of the heat capacity, surface tension, viscosity striking. One of the interesting features observed in high densities. - How to make a step-down transformer
Transformer is a device that is a core made from electrical steel sheet, which is wound with insulated wire. The voltage drop is due to the ratio of the number of turns of the primary and secondary windings. - How to distinguish platinum
Platinum takes a leading place among the noble metals, along with gold and silver. This beautiful white-silvery metal is quite rare and has properties that make it ideal for manufacture of fine jewelry. An inexperienced person can be difficult to distinguish platinum from other metals, for example, from white gold. - How to measure the inductance of the coil
Coil inductance are elements in the marking which parameters are not usually specified. Moreover, it often coils wound independently. In both cases, to determine the inductance of the coil is possible only by means of its measurement. It can be carried out by various methods, involving the use of a variety of complexity of the equipment. Some of these methods are laborious and require calculations. But active LC meters free from these shortcomings allow you to measure inductance , quickly and without additional calculations. - How to measure the cube
The cube or hexahedron is a geometric figure that is a regular polyhedron. Moreover, each of its faces is a square. In order to solve the problem on a cube, in solid geometry, we need to know the basic geometric parameters such as edge length, surface area, volume, radii of the inscribed and circumscribed spheres. - How to solve the problem about the area of a triangle
One of the figures covered math and geometry is a triangle. Triangle - a polygon that has 3 vertices (corners) and 3 sides; part of the plane bounded by the three points United in pairs in three segments. There are many tasks associated with finding the different values of this figure. One of them is square. Depending on the initial data of the problem there are several formulas for determining the area of a triangle. - How to make a crystal of copper sulphate
Blue crystals of copper sulfate are extremely beautiful. Experience in cultivation may be a long time to interest your preschooler and even the school child will love to watch grow on the string of crystals. For high school student this can serve as an introduction to one of the most interesting science — crystallography. - How to calculate fractions
The number composed from a certain number of share units, in arithmetic, is called a fraction. It usually consists of two parts - the numerator and the denominator. Each of them is an integer. Literally the denominator shows how many parts the unit is divided, and the numerator how many of these parts took. - How to identify amber
Amber is one of the most respected human stones, known since time immemorial. Fashion it still fails. Often there are imitations and fake amber, so it is advisable to buy jewelry made from this stone from trusted and reliable vendors. It will also be useful the ability to determine real amber. - How to solve the anagram
Literary criticism - science is difficult and includes many different techniques designed to diversify ordinary language. Anagram is one of such techniques, the essence of which is that when you rearrange the letters of one word get more. Single method in order to solve the anagramdoes not exist, because the principle of its construction and complexity depend on the imagination of the author. - How to display the percentage
In any sphere of activity, the question may arise, how to get percentage. It's pretty simple arithmetic operation that you want to remember to everyone. There are several variants of the calculation, allowing to master the operation and everyone can, the main thing is to remember the sequence of actions. - How to know the wire size
Not uncommon when you want to determine the unknown cross-sectional area of the wire. It is easy to do, and there are several ways. Unfortunately, to use the simplest of them – to find out the cross section of the markings on the insulation is almost never possible: the marking or missing, or worn to the extreme. All other ways reduced to clarify with the help of improvised means. - How to calculate the hypotenuse
If you need to find the length of the hypotenuse of a right triangle and known length of both sides, you can use the Pythagorean theorem. If you know the length of only one leg and one and any sharp corners, for you too, all is not lost.