Despite the invention of the decimal system, which is now used by the whole world, American and English measures of length are often found in everyday life. Let's take the diagonal of the TV. In the passports of equipment, warranty cards, everywhere the size is indicated in inches. The same applies to the diameter of pipes, sizes of tools, bolts, nuts. In order not to look stupid in situations with unfamiliar quantities, it is necessary to have an idea about the main ones.

Measures of length

Our ancestors did not have digital and magnetic instruments capable of measuring the desired value. Therefore, for convenience, they used the measure of their own body, that is, what they always have with them. These were feet, fingers, elbows, steps, palms.

• Mile as the most popular unit, adopted around the world to indicate the distance of air and land routes.

1 mile (mil) = 1609 m

1 nautical mile = 1852 m

• The basic value of the American system is considered to be a foot.

1 foot (ft) = 30.48 cm

The meaning of the foot comes from England. This value measured a distance equal to 16 feet and was called a stock (stock).

• Size inch was popular in all European countries before the introduction of the SI system. It was calculated by the length of the joint of the thumb or its width at the base.

1 inch (in) = 25.4 mm

There is an opinion that the size of an inch was determined by three grains of barley, laid along one after another. According to another version, the component of an inch was 1/36 of a yard, which was established by King Henry I in 1101. Its length was equal to the distance from the middle finger of the right hand to the tip of his nose.

• The yard was originally taken as the average stride length.

1 yard (yd) = 0.9144 m

• Line - used in the military to indicate the caliber of a weapon.

1 line (ln) = 2.12 mm

• league. The value of the league has long been used in naval battles to determine the distance of a cannon shot. Later it began to be used for land and postal affairs.

1 league = 4.83 km

Measures rarely used in everyday life

1 mil = 0.025 mm

1 hand = 10.16 cm

1 genus = 5.029 m

1 chain = 20.12 m (for surveyors) and 30.48 m (for builders)

1 furlong = 201.17 m

1 faton = 1.83 m

1 el = 1.14 m

1 pace = 0.76 m

1 qubit = 46-56cm

1 span = 22.86 cm

1 link = 20.12 cm (for surveyors) and 30.48 cm (for builders)

1 flieger = 11.43 cm

1 nail = 5.71 cm

1 barleycorn = 8.47 mm

1 dot = 0.353 mm

1 cable = 219.5 m (in England it is 183 m)

The most popular units of measurement

The USA is the only developed country that has abandoned the metric system. In addition to the States, 2 more countries do not use the SI system, these are Liberia and Myanmar.

Once in this country, do not be surprised if in cold, wet weather you ask how many degrees outside and they answer you that plus 32. Just 0 degrees Celsius, this is American 32 Fahrenheit. When approaching a gas station, be sure to convert liters to gallons. Our 3.78 liters corresponds to one gallon.

• Barrel- a measure of volume for bulk materials and liquids.

Translated from English means barrel. In the world, the calculation of oil in barrels is recognized as the most convenient, so oil companies set prices in dollars per barrel.

1 barrel (bbl) = 158.9 liters

1 dry barrel = 115.6 liters

Especially for calculating the volume of beer in the UK, the concept of a beer barrel was introduced. Its value changed over time and depended on the type of drink (ale or beer). The value was finally established in 1824 and amounted to 163.66 liters per 1 barrel.

• Bushel- a measure of volume for dry matter in agriculture (measured the volume of grain, vegetables, fruits). In international trade, a bushel is accepted as a container weighing 18 kg.

1 bushel (bu) = 35.24 liters

• Gallon- the same as the barrel. A gallon is in turn divided into a pint and an ounce.

1 fluid gallon (gl) = 3.79 dm3

1 gallon for bulk solids (gl) = 4.4 dm 3

1 pint = 1/8 gallon = 0.47 dm3

1 ounce = 1/16 pint = 29.57 ml

An ounce has retained its value since ancient times and was approximately equal to 30 g. In the American system, the concept of an ounce is widely used in the pharmaceutical and jewelry business.

• Quart- a unit of measure for the volume of a container, equal to ¼ gallon

1 quart for liquid = 0.946 liters

1 quart solids = 1.1 liters

Measures of area

The square acre has found the greatest distribution in world literature..

Its original designation served to calculate the area of ​​land that one peasant with one ox could cultivate.

Converting the value of acre to the SI system is very simple. If we divide the number by 10, we get the result in meters. And if you divide by 2 - in hectares.

1 inch (sq. in) = 6.45 cm2

1 foot (sq. ft) = 929 cm 2

1 yard (sq.yd) = 0.836 m2

1 mile (sq.mi) = 2.59 km2

1 acre (a) \u003d 4046.86 m 2

Measures of volume

Why define volume?

• to describe the capacity of household appliances
• for shipping containers
• to determine the amount of gas
• to describe the capacity of commercial warehouses

The most commonly used measure of three-dimensional space is the foot. A cubic foot is defined as the volume of a cube, with an edge of 1 foot. Less commonly used values ​​are yard and inch.

To get a cubic volume, you need to multiply the length, height and width.

1 ton (register) = 2.83 m 3

1 yard = 0.76 m 3

1 foot \u003d 28.32 dm 3

1 inch = 16.39 cm3

Measures of weight

• The pound is used as a measure of weight and to describe mass.

In the US, the pound is used to express pressure per square inch. The pound is also used to describe the weight of ammunition (cartridges, shells, bullets).

To convert pounds to kilograms, you need to divide the number of pounds by 2.2

1 lb (lb) = 453.59 g

• An ounce is a measure of weight that has found application in jewelry, banking, to determine the weight of precious metals and stones, as well as in the pharmaceutical business.

To convert an ounce to kilograms, you need to divide its amount by 35.2

1 ounce (oz) = 28.35 g

• A stone is a unit of measure that is used to describe the weight of the human body..

1 stone (st) = 6.35 kg

• A short ton is a unit of weight equivalent to 2,000 pounds.. In the USA, the long ton is also known, but practically not used, which is equal to 2240 trade pounds.

1 short ton = 907.18 kg

1 long ton = 1016 kg

If you are going to America, check out the local standard of measures. Thus, you will avoid awkward situations and choose the right question that interests you. For this, it is not necessary to memorize numbers. It is enough to download a simple converter to your phone.

Length should be understood as a physical quantity, which is a characteristic of the length of lines in numbers. This concept has several definitions that you should be aware of. Units, tools and devices for measuring length are also different. Therefore, in this article we will tell you how and how to measure the length.

What is length

As we have already said, the concept of length should be understood as a physical quantity. In the narrow sense of the word, it means the size in the longitudinal direction. That is, length can be called the distance between two points of an object that are as far as possible from each other. However, it is important to note that this distance should be measured horizontally, and not vertically, as in the case of height measurements.

In physics, the concept of length is equivalent to the term "distance". It should also be noted that in the vast majority of measurement systems, length is the main unit of measure, with which other units are established. In the international system of units, the unit of length is the meter.

Length units

First of all, it is necessary to say about the metric system, which to this day is the most convenient because of its simplicity. It is based on the unit of measurement meter, and the rest are multiple powers of ten from it. For example, a kilometer is 10 meters cubed. This system greatly simplifies the calculations.

In Russia, a person was a measure of length for a long time. This can be judged by the names of the measures, including span, elbow, sazhen and others. A span is a measure corresponding to the distance between the index and thumb in an extended position, an elbow is the length from a clenched fist to the bend of the elbow, and a fathom is from the end of the fingers of one hand to the end of the other.

From various works of literature, we also know such a unit of distance as a verst. It corresponds to today's 1,066.8 meters. In Ancient Russia, miles were boundary and travel. The first were used to measure land, the second - distances or paths.

In England and America, other units were used. For a long time in Britain, the following units of length existed:

• mile;
• inch.

The yard is not included in the international system of units and is equal to 0.9144 meters. The mile came from ancient Rome, where it was equal to a thousand double steps of a soldier. This unit is still used in a number of countries where the metric system of measures is not used. In different countries, its value is different. In England, it corresponds to 1.6 kilometers. The foot is also not included in the international system and corresponds to 0.3048 meters. An inch, which is used today in the United States and Britain, is equal to 2.54 centimeters.

In addition, there is also a nautical system for measuring length, which is based on the unit of measurement - the nautical mile. It is equal to the length of one minute of the earth's ellipsoid meridian arc. Its length is a variable and depends on latitude. The international nautical mile is 1852 meters.

Length measurement tools

The simplest tool for measuring length is a ruler, which is a narrow plate. On it, as a rule, there are divisions corresponding to the unit of measurement. It can be a millimeter, centimeter, inch, etc. In cartography and geometry, this tool is used only for the purpose of drawing straight lines. Other instruments are used to measure distances, and measuring length with a ruler is considered insufficiently accurate.

Another common tool for measuring the length of an object is a tape measure. It is a tape on a reel, which is wound into the body using a special mechanism. It also has divisions in the form of strokes in accordance with the unit of measurement. Most often there are roulettes 3 or 5 meters long. However, there are also instruments that allow you to measure lengths up to 100 meters.

It should also be said about the end block of length, which is often referred to as KMD. It is an exemplary measure of length (0.5-1000 millimeters), which is made in the form of a round cylinder or a rectangular parallelepiped. Gauge block is designed to store and transmit a unit of length. It is with its help that the verification and establishment of the size of measuring instruments takes place.

Distance measuring instruments

The so-called rangefinder is a device for determining the distance from the observer to a certain object. Rangefinders are active and passive. The former include laser, sound and light rangefinders, and the latter are devices that use matching an object to a specific sample or optical parallax.

Separately, we should talk about such a device as a radio range finder. It helps to determine the distance using radio waves. This device is used in military affairs, in space and air navigation and in other areas. This device sets the time it takes for a radio wave to travel from it to a specific object and back. Thus, the distance to a given object is directly proportional to the time interval.

According to the measurement method, such devices are divided into pulse radio range finders and phase ones. In the first case, the delay time of the reflected signal is measured, while in the second, the number of wavelengths that fit in the signal path is determined.

It is important to add that very small distances are usually measured using so-called measuring microscopes. And very large ones are installed by means of satellite and radio navigation systems for measuring length.

The size of the penis is a very important nuance for a man. Every guy at least once measured his body or is going to do it.

Getting accurate results is a simple task, you just need to follow the rules. But most men make mistakes and do not know how to properly measure a penis, which often leads to an incorrect result.

In contact with

Statistics of average sizes depending on age

Age	Length (cm)	Thickness (cm)
12-13	10.5-13	7.5-8
14-15	15-16	9.5-10.5
16-17	15.5-16	11.5-12
18+	15.5+	12+

After 18 years, the penis of a man is already formed and has reached its maximum value.

Statistics that were carried out to find out what is the average penis length in men:

Video about the statistics and size of the male organ:

Why is it needed

Basically, it's done for yourself, to calm the ego.

For the first time, such an idea comes back in school years. The problem with the length of the penis worries all schoolchildren in the world. And often young guys do not know how to measure it.

The main reason why you need to know the size of your phallus is to choose the right size condom. There are a number of models that will be large or small in relation to the penis. In order to avoid discomfort or unexpected outcomes, it is better to know in advance how to measure a penis and remember by heart the size of your “comrade”.

What conditions to follow

Men think that in order to measure a “friend”, it is enough to wait for an erect state and attach a ruler to it. This approach will give incorrect results. There are a number of factors and favorable conditions for obtaining correct measurements.

• Measure your penis only at room temperature. If the room is cold, then the phallus will decrease in size.
• Stress, excitement affect the size of the phallus. During measurements, you should be calm and full of energy.
• Z chambers to produce only in a state of full excitation to get the best possible erection.

It is best to measure in the morning, on a day off. During this period, the body is full of strength and the erection will be maximum.

How to measure penis length

The correct measurement of penis length occurs in several stages. The main thing is that all conditions are met.

1. Measurements are taken standing, not sitting. In this state, the penis is not retracted and the entire shaft is visible.
2. The penis should be parallel to the ground. To do this, you can tilt it down.
3. For measurements, use a ruler or a centimeter.
4. We apply one edge to the pubis, and the second to the extreme point of the head. The result will be the length of the penis.

Many measure the penis from the testicles - this is wrong. Start the measurement from the pubic area.

How to measure penis diameter

№4 - Pharmacology. There are a number of pills on sale, their task is to increase the size of the penis.

Useful video

Video about penis size:

Value is something that can be measured. Concepts such as length, area, volume, mass, time, speed, etc. are called quantities. The value is measurement result, it is determined by a number expressed in certain units. The units in which a quantity is measured are called units of measurement.

To designate a quantity, a number is written, and next to it is the name of the unit in which it was measured. For example, 5 cm, 10 kg, 12 km, 5 min. Each value has an infinite number of values, for example, the length can be equal to: 1 cm, 2 cm, 3 cm, etc.

The same value can be expressed in different units, for example, kilogram, gram and ton are units of weight. The same value in different units is expressed by different numbers. For example, 5 cm = 50 mm (length), 1 hour = 60 minutes (time), 2 kg = 2000 g (weight).

To measure a quantity means to find out how many times it contains another quantity of the same kind, taken as a unit of measurement.

For example, we want to know the exact length of a room. So we need to measure this length using another length that is well known to us, for example, using a meter. To do this, set aside a meter along the length of the room as many times as possible. If he fits exactly 7 times along the length of the room, then its length is 7 meters.

As a result of measuring the quantity, one obtains or named number, for example 12 meters, or several named numbers, for example 5 meters 7 centimeters, the totality of which is called composite named number.

Measures

In each state, the government has established certain units of measurement for various quantities. A precisely calculated unit of measurement, taken as a model, is called standard or exemplary unit. Model units of the meter, kilogram, centimeter, etc., were made, according to which units for everyday use are made. Units that have come into use and approved by the state are called measures.

The measures are called homogeneous if they serve to measure quantities of the same kind. So, grams and kilograms are homogeneous measures, since they serve to measure weight.

Units

The following are units of measurement for various quantities that are often found in math problems:

Measures of weight/mass

• 1 ton = 10 centners
• 1 centner = 100 kilograms
• 1 kilogram = 1000 grams
• 1 gram = 1000 milligrams

• 1 kilometer = 1000 meters
• 1 meter = 10 decimeters
• 1 decimeter = 10 centimeters
• 1 centimeter = 10 millimeters

• 1 sq. kilometer = 100 hectares
• 1 hectare = 10000 sq. meters
• 1 sq. meter = 10000 sq. centimeters
• 1 sq. centimeter = 100 sq. millimeters

• 1 cu. meter = 1000 cubic meters decimeters
• 1 cu. decimeter = 1000 cu. centimeters
• 1 cu. centimeter = 1000 cu. millimeters

Let's consider another value like liter. A liter is used to measure the capacity of vessels. A liter is a volume that is equal to one cubic decimeter (1 liter = 1 cubic decimeter).

Measures of time

• 1 century (century) = 100 years
• 1 year = 12 months
• 1 month = 30 days
• 1 week = 7 days
• 1 day = 24 hours
• 1 hour = 60 minutes
• 1 minute = 60 seconds
• 1 second = 1000 milliseconds

In addition, time units such as quarter and decade are used.

• quarter - 3 months
• decade - 10 days

The month is taken as 30 days, unless it is required to specify the day and name of the month. January, March, May, July, August, October and December - 31 days. February in a simple year has 28 days, February in a leap year has 29 days. April, June, September, November - 30 days.

A year is (approximately) the time it takes for the Earth to complete one revolution around the Sun. It is customary to count every three consecutive years for 365 days, and the fourth following them - for 366 days. A year with 366 days is called leap year, and years containing 365 days - simple. One extra day is added to the fourth year for the following reason. The time of revolution of the Earth around the Sun does not contain exactly 365 days, but 365 days and 6 hours (approximately). Thus, a simple year is shorter than a true year by 6 hours, and 4 simple years are shorter than 4 true years by 24 hours, that is, by one day. Therefore, one day (February 29) is added to every fourth year.

You will learn about other types of quantities as you further study various sciences.

Measure abbreviations

Abbreviated names of measures are usually written without a dot:

Kilometer - km Meter - m Decimeter - dm centimeter - cm Millimeter - mm	Measures of weight/mass ton - t centner - c kilogram - kg gram - g milligram - mg
Area measures (square measures) sq. kilometer - km 2 hectare - ha sq. meter - m 2 sq. centimeter - cm 2 sq. millimeter - mm 2	cube meter - m 3 cube decimeter - dm 3 cube centimeter - cm 3 cube millimeter - mm 3
Measures of time century - in year - y month - m or mo week - n or week day - from or d (day) hour - h minute - m second - s millisecond - ms	A measure of the capacity of vessels liter - l

Measuring instruments

To measure various quantities, special measuring instruments are used. Some of them are very simple and are designed for simple measurements. Such devices include a measuring ruler, tape measure, measuring cylinder, etc. Other measuring devices are more complex. Such devices include stopwatches, thermometers, electronic scales, etc.

Measuring instruments, as a rule, have a measuring scale (or short scale). This means that dash divisions are marked on the device, and the corresponding value of the quantity is written next to each dash division. The distance between two strokes, next to which the value of the value is written, can be further divided into several smaller divisions, these divisions are most often not indicated by numbers.

It is not difficult to determine which value of the value corresponds to each smallest division. So, for example, the figure below shows a measuring ruler:

The numbers 1, 2, 3, 4, etc. indicate the distances between the strokes, which are divided into 10 equal divisions. Therefore, each division (the distance between the nearest strokes) corresponds to 1 mm. This value is called scale division measuring instrument.

Before you start measuring a quantity, you should determine the value of the division of the scale of the instrument used.

In order to determine the division price, you must:

1. Find the two nearest strokes of the scale, next to which the magnitude values ​​are written.
2. Subtract the smaller value from the larger value and divide the resulting number by the number of divisions in between.

As an example, let's determine the scale division value of the thermometer shown in the figure on the left.

Let's take two strokes, near which the numerical values ​​of the measured quantity (temperature) are plotted.

For example, strokes with symbols 20 °С and 30 °С. The distance between these strokes is divided into 10 divisions. Thus, the price of each division will be equal to:

(30 °C - 20 °C) : 10 = 1 °C

Therefore, the thermometer shows 47 °C.

Each of us constantly has to measure various quantities in everyday life. For example, to come to school or work on time, you have to measure the time that will be spent on the road. Meteorologists measure temperature, atmospheric pressure, wind speed, etc. to predict the weather.

The basic unit of length is the meter (m). Initially, the distance between two strokes on a specially made platinum-iridium rod 102 cm long, stored at the International Bureau of Weights and Measures in Paris, was taken as a sample (standard) of a meter (Fig. 14). The material and cross-sectional shape of the rod and its storage conditions were chosen in such a way as to best ensure the stability of the sample. In particular, measures were taken to maintain a constant temperature of the rod. Carefully made secondary standards - copies of this sample - are stored in the institutes of measures and weights of different countries.

Rice. 14. Initial standard of the meter (general view and section)

It was supposed to make a sample of a meter equal to one forty-millionth of the length of the earth's meridian. When the insufficient accuracy of measurements on the earth's surface became clear, they did not replace the manufactured sample or make corrections based on more accurate measurements, but decided to keep the sample itself as a unit of length. This pattern is about 0.2 mm smaller than 1/40,000,000 of a meridian.

In addition to this basic unit, other units are also used in science and technology - decimal multiples and submultiples of a meter:

kilometer (1 km=1000 m);

centimeter (1 cm=0.01 m);

millimeter (1 mm=0.001 m);

micrometer (1 µm=0.001 mm=0.000001 m);

nanometer (1 nm=0.000000001 m).

In England, the USA and some other countries, the so-called English measures of length are widespread:

inch = 25.4mm;

ft = 12 inches = 304.8 mm;

land mile ("statute") = 1609 m;

nautical mile ("Admiralty") = 1852 m (the length of one minute of the arc of the earth's meridian).

The old Russian measures of length were:

vershok = 4.445 cm;

arshin \u003d 28 inches \u003d 16 inches \u003d 0.7112 m;

sazhen \u003d 3 arshins \u003d 2.1336 m;

verst = 500 fathoms = 1.0668 km;

Russian mile = 7 versts = 7.4676 km.

The abundance of different units of length (as well as units of other physical quantities) is very inconvenient in practice. Therefore, international standard definitions of units of all physical quantities were developed. The collection of these definitions is called the SI system of units (from the words Systeme Internationale - International system). Since 1963, in the USSR and a number of other countries, SI has been recommended for use in all fields of science and technology.

According to this system, a meter is defined as a length equal to 1,650,763.73 wavelengths of orange light emitted by a special lamp in which krypton-86 gas glows under the action of an electric discharge. The number of lengths of will is chosen so that this unit of length coincides as closely as possible with the Parisian meter. Therefore, the length was not chosen as a unit, on which any round number (for example, one million) of wavelengths would fit. This new unit of length can be reproduced (optically) with greater accuracy than the archival sample. It is very convenient that in order to reproduce a unit of length, one does not need to refer to a single stored sample, but it is enough to make a special krypton lamp and observe the light emitted by it.

In practice, to measure length, including to measure the distances between two positions of a point on a trajectory, copies of secondary standards are used: rods, rulers or tapes with divisions equal to the length of the standard, or part of it (centimeters, millimeters). When measuring, the beginning of the measuring ruler is combined with one end of the measured segment and its division is noted, against which the second end of the segment will be. If the second end does not coincide with any of the divisions of the ruler, then “by eye” it is estimated at what fraction of the distance between the divisions it turned out to be.

Rice. 15. Vernier caliper

To reduce the inevitable reading error, various auxiliary devices are used. On fig. 15 shows one of them - a vernier mounted on a caliper. The vernier is an additional scale that moves along the main scale. Noius divisions are less than divisions of the main scale by 0.1 of their size; for example, if the division of the main scale is 1 mm, then the division of the vernier is 0.9 mm. The figure shows that the diameter of the measured ball is greater than 11 mm, but less than 12 mm. To find how many tenths of a millimeter the remaining fractional part of the division is, look at which of the strokes of the vernier matches any of the strokes of the main scale. In our drawing, this is the ninth stroke of the vernier. This means that the eighth, seventh, etc. strokes of the vernier will be ahead of the previous strokes of the main scale closest to them by 0.1 mm, 0.2 mm, etc., and the initial stroke of the vernier will be 0.9 mm ahead of the nearest to him the previous stroke of the main scale. It follows that the diameter of the ball is equal to as many whole millimeters as they fit from the beginning of the main scale to the beginning of the vernier scale (11 mm), and as many tenths of a millimeter as the vernier divisions fit from the beginning of the vernier scale to the matching strokes (0.9 mm) . So, the measured diameter of the ball is 11.9 mm.

Thus, the vernier allows you to measure distances with an accuracy of 1/10 of the scale division.