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🍜 | Higashi Osaka / Fuse A restaurant where you can enjoy the big jumbo-sized specialty kitsune udon!Affection Udon Nadeshiko


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Higashi-Osaka / Fuse A restaurant where you can enjoy the big jumbo-sized specialty Kitsune Udon!Affection Udon Nadeshiko

 
If you write the contents roughly
It is a volume that is likely to be torn off due to its size and weight when lifted.
 

"Ai Udon Nadeshiko" has a shop just a short walk south of Fuse Station in Higashi Osaka.The famous udon menu ... → Continue reading

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WEB media "V-TRIP" where cameramen and video creators travel around the country to introduce tourist and gourmet information on hotels and resorts all over Japan, focusing on videos.


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Size

Size

size

General concept
Person's name

Scythian

etc.

footnote

  1. ^  "Size"

外部 リンク

  • Size .COM --A site that introduces the sizes of all things.

重 さ

重 さ(Weight, weight) orweight(Juryo, weight) has two meanings depending on the context of the object.massWhen it means (mass) and when it works on an object重力The size of, i.e.PowerMay mean (force).Once in the engineering field, the mass of an object and the force it exerts (or)load) Was not strictly distinguished, and discussions and calculations were conducted ()Gravity unit system), But now it is strictly distinguished.

Ambiguity of "weight" and "weight"

"Weight" is an everyday language (Japanese), and is used in general everyday usage.Physical quantityThere are two different meanings.One is of the objectmass(Unitskilogram(Kg)), and the other works on objects重力The size of, i.e.Power(UnitsNewton(N)) means[1]..These two meanings are used vaguely in our daily lives.That is because in everyday life on Earth it is not necessary to distinguish between mass and the force it exerts on gravity.Many people use the word "weight" in various situations even when they grow up.Both mass and gravitydensityAlsopressureHowever, all of them are expressed as "weight", and "weight" is "weight".[2].

In elementary school, weight is taught only the meaning of mass[3]..On the other hand, in junior high school, "weight" is taught to be force, and is distinguished from mass.And it is taught that the unit of mass is kilogram (kg) and the unit of weight is Newton (N).

The Chinese expression for "weight" is "weight" (also in English, weight), but this also means the meaning and force of mass (weight).load) Is the same as "weight" in that it has two meanings.for example,Road Transport Vehicle ActIt is,Vehicle total weightThe word of the vehicle totalmassIt is used in the meaning of (Vehicle total weightSee section).

Ambiguity in English and the United States

The general term for weight and weight in English is weight, but this is also confusing because it has both the meaning of mass and the meaning of force (load).[4].

Even in the United States, the term weight, as a commercial and everyday term, is often mistakenly used to mean mass.in this regard,NISTIt is,International System of Units International DocumentsIn the US version of1901 CGPM StatementContinues to give attention in relation to[Note 1][Note 2].

Clarification of the word weight (decision of the General Conference on Weights and Measures)

1901 times of 3 yearsInternational Weights and Measures General Assembly(CGPM) isweight(Buddha: weight,British: weight In order to eliminate the ambiguity of the word), the following statement was issued.

Statement on the unit of mass and the definition of weight;gn Agreement value (CR, 70)

Considering the decisions contained in the metric prototype approval document unanimously adopted by the General Conference on Weights and Measures at the meeting on September 1889, 9.

Sometimes mass (Buddha: mass gain,British: mass), Sometimes a mechanical force (Buddha: strength,British: strength) Used for weight (Buddha: weight,British: weightConsidering the need to remove the ambiguity that still remains in everyday usage of the meaning of the term), the General Conference on Weights and Measures

1. Kilogram is a unit of mass, which is equal to the mass of the International Prototype of Kilogram.[Note 3]

2. The term "weight" refers to a quantity of the same nature as "force".The weight of an object is the mass of that objectAcceleration of gravityThe product of, in particular, the standard weight of an object is the product of the mass of that object and the standard gravitational acceleration.

3. The value adopted by the General Conference on Weights and Measures for the value of standard gravitational acceleration is 980.665 cm / s.2 And already specified in the laws of some countries[Note 4].

Make a statement.[5]

This statement clarified the meaning of the word weight and eliminated the confusion with the word mass, but it can still be confused in everyday use.

Overview

When you hold an object in your hand, you feel the "weight" of that object.地球 OfgravitationalByHandToPowerThis is to exert.In addition, the reason why you feel "weight" when you try to shake a suspended bell by hand is that the inertial force exerts a force on your hand.In both cases, we describe them as "heavy" because we have long known from experience that gravity due to gravitational acceleration and inertial force due to acceleration are closely related.On earthmassIs 1kgGravity applied to the object is about 9.8N (Newton), And this force is 1kgw (Kilogram-force) Or 1kgf.

Since gravity changes in proportion to the acceleration of gravity, the same object will have different weights (gravity) on different celestial bodies, and even on the earth, it will have different weights (gravity) depending on the location.Therefore, it is easy to measure the weight using gravity.Spring scaleWhen using, the standard is set.

It has been used since ancient times.BalanceWeight weighed inIs constant regardless of gravitational acceleration, in this caseGeneral relativity OfEquivalence principleAccording to it, the weight and the mass are exactly the same.Also, of the substanceInertial forceThe "weight" that means "weight" is also constant regardless of the gravitational acceleration.

Weight / weight / mass

As mentioned above, the weight重力Since gravity differs depending on the acceleration of gravity, weight is not a property peculiar to each object.However, the reason why weight and weight have been equated for a long time is that an object is pulled downward by a force of a magnitude almost proportional to its mass on the earth.PowerWas regarded as the nature of the objectweightThis is because it was called (that is, mass).This way of thinking corresponds to a measuring instrument such as a spring that a human holds in his hand and estimates the weight from gravity, or a spring that weighs with the scale of a spring that extends due to gravity.This utilizes the fact that the gravitational acceleration is almost constant on the earth, and spring scales are widely used because they are small and convenient.

On the other hand, the weight is like the weighing and inertial force of the balance.重力notweightIf you think of it as weightmassHas been proved in numerous experiments to be an exact match.The proportional force between gravity due to gravitational acceleration and inertial force due to accelerationNewtonNewton knew well that the weight and mass of the balance would be the same because it was measured so accurately in his time, but he did not use the word weight carefully and called it "dense thing". It was an expression, and I didn't make the word mass.This is because Newton himself was not sure if the weight and mass would exactly match.Later physicists were similarly uncertain, so they used "mass" as an alternative to weight, butア イ ン シ ュ タ イ ンIt is a well-known story that Einstein was able to come up with the equivalence principle because it was clarified by experiments that the weight and mass match with considerable accuracy in the era of.

In this way, it is now known that weight and mass are exactly the same (only on a balance), but in physics etc., "mass" is used to eliminate ambiguity from the misunderstanding that weight is measured by gravity. Use the word.

Precautions when weighing

In fact, when the spring scale was invented, it was practiced to handle the weight of an object based on gravity.It can be said that the theory by Newton et al. Confirmed that it was not a problem in practical use, and at the same time showed that there were slight differences, and that various errors occurred when it was not on ordinary ground.In reality, the magnitude of gravity varies from region to region even on the ground.

As mentioned above, it is usually not difficult to think of gravity as mass on the earth, but it can be bad in practice.For example, the surface of the earthvacuumBecause it is not, the objects that exist there are alwaysbuoyancyIt is necessary to correct the apparent gravity by the generated buoyancy.Human activity is usually done in the air, which is much less dense than most objects that humans consciously handle, so this is usually rarely noticed.However, because of this, the feeling that there is no weight of air is circulating.Also, for something that rises like a hot air balloon, "LightnessThere was also a judgment in the past that it had the property of.

Derived meaning

Derived meaning is that it represents the significance of abstract things.In this case, the words "weight" and "heavy (put)" are often used.When it comes to weight, the impression that it "hangs on" reflects the nature of weight.Also called emphasis.

Unit of weight

footnote

[How to use footnotes]

注 釈

  1. ^ NIST SP 330 (SI) 2019 Edition p.46, Below Editors' note: In the United States the term “weight” is used to mean both force and mass. In science and technology this declaration is usually followed, with the newton (N) the SI unit of force and Thus weight. In commercial and everyday use, and especially in common parlance, weight is often (but incorrectly) used as a synonym for mass, the SI unit of which is the kilogram (kg). The term is used to mean both force and mass.In the field of science and technology, this declaration (1901 CGPM) is usually followed (the unit is force, and therefore the SI unit of weight, Newton (N)).In commercial and everyday use, especially as a profane, the word weight is often (but incorrectly) used as a synonym for mass (SI unit is kilogram (kg)). ..
  2. ^ NIST SP330 (1981)p.18, 3d CGPM 1901, USA Editors' note. "In the USA, ambiguity exists in the use of the term weight as a quantity to mean either force or mass. In science and technology this declaration (CGPM (1901)) is In commercial and everyday use, weight is often usedn in the sense of mass for which the SI unit is the kilogram. " There is ambiguity as to whether it means force or mass.In the field of science and technology, this 1901 CGPM statement is usually followed (in Newton).In commercial and everyday use, the word weight is often used to mean mass (in kilograms).
  3. ^ This definition was abolished by the 2018th General Conference on Weights and Measures (Resolution 26) in 1.
  4. ^ This gn The value of is a unit that is currently excludedKilogram-forceIt is an agreement reference value for calculating.

Source

  1. ^ Akito Arima and 70 others, (junior high school textbook) Science World 183, p.2020 "In our daily lives, we sometimes use" weight "to mean both mass and gravity.But in science, weight and mass are used in different ways. , Certified on March 3, 2,Dainippon Books,ISBN-978 4-477031750
  2. ^ How to Teach "Mass" -Returning to Newton's Definition of Mass- Kazuo Yoshino and Fumiko Koji, Bulletin of Faculty of Education, Niigata University Vol. 10, No. 2, p.127, 6. No inconvenience in daily life without distinguishing between gravity and mass, accepted on October 2017, 10
  3. ^ Akito Arima and 58 others, "Fun Science 166rd Year", p.2019, Monoshuru and Weight, "Weight is expressed in terms of grams ...", Certified on March 3, 5, Dainippon Tosho,ISBN 978-4-477-03122-4 , February 2021, 2 Reprint Issued
  4. ^ The American Heritage Dictionary, Second College Edition, p.1371, Houghton Mifflin Company, 1982, ISBN 0-395-32943-4 1) A measure of the heaviness or mass of an object. 2) The gravitational force exerted by the earth or another celestial body on an object, equal to the product of the object's mass and the local value of gravitational acceleration.
  5. ^ [1] BIPM Author,National Institute of Advanced Industrial Science and Technology International System of Units (SI) 9th Edition (2019) Japanese Edition, National Institute of Advanced Industrial Science and Technology, National Institute of Advanced Industrial Science and Technology, March 2020, pp. 3-126. 

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