CN111272250A - Method for measuring volume and density of solid object - Google Patents

Abstract

The invention relates to a method for measuring the density of an object, in which fine particles of uniform texture and known mass (m) and volume (V) are prepared beforehand₁) The container is filled with fine particles, and the fine particles are weighed to obtain the total mass m₁According to rho_{Particulate matter}＝(m₁‑m)/v₁Obtaining the density rho of the fine particles_{Particulate matter}Weighing and recording the mass m of the measured object_{Object to be measured}Transferring part of fine particles out of the container for storage, retaining a few fine particles at the bottom of the container, placing the solid matter to be measured into the container, filling the container with the fine particles transferred out of the container, weighing and recording the mass m of the remaining fine particles taken out of the container₂And is in v_{Object to be measured}＝m₂/ρ_{Particulate matter}Calculating the volume of remaining fine particles to obtain v_{Object to be measured}And calculating the object to be measured based on the calculated dataThe density of (c). The invention satisfactorily solves the problems of volume and density measurement of solid objects with complex shapes, and has higher measurement precision.

Description

A method for measuring the volume and density of solid objects

technical field

The invention relates to a method for measuring the density of objects. It should be noted that the present invention is not suitable for measuring the density of hollow objects.

Background technique

In daily life, we usually measure the volume of solid substances to calculate the density, which can be used to evaluate the quality and purity of the substance or to judge the authenticity of the object, such as the specific gravity of wheat and corn, granular plastics, granular fertilizers, etc. true and false, etc.

The density of a substance is the mass of the substance per unit volume. Therefore, to measure the density of a substance, it is usually necessary to measure the mass and volume of the substance. The mass of a substance is relatively easy to measure and can be obtained by weighing it with a balance. However, the measurement of the volume of an object is more complicated. For a regular object, the volume of the object can be calculated by measuring the external size of the object. For non-water-soluble solid substances, it can also be measured by immersion in water. However, it is very difficult to measure the volume of granular solid substances that are easy to absorb water, cannot be immersed in water or liquid, or have irregular surfaces and small volumes, such as clods, cork, sponges, granular fertilizers, etc. Therefore, it is very important to find a way to measure the volume and density of solid substances.

SUMMARY OF THE INVENTION

The present invention provides a method for measuring the density of solid objects that overcomes the general deficiencies of the prior art.

The method for measuring the density of solid objects of the present invention is to prepare in advance fine particles with uniform texture and a container with a mass of m and a volume of v. The measurement steps are as follows:

(1) Fill the container with fine particles and make it flush with the upper edge of the container, weigh and record the total mass of the fine particles and the container as m ₁ ;

(2) Calculate the density ρ _{particles of} the fine particles in step (1) according to formula ①,

ρ _{particulate matter} = (m ₁ -m)/v ₁ ①;

(3) Weigh and record the mass m _{of the measured object} ;

(4) Transfer some fine particles out of the container for storage, leave only 2-3cm thick fine particles at the bottom of the container, put the solid substance to be measured into the container, and make the highest point of the solid substance to be measured slightly lower than the container the upper edge of the container, and then fill the container with the fine particles transferred from the container, and keep the surface of the fine particles flush with the upper edge of the container;

(5) Weigh and record the mass m ₂ of the remaining fine particles taken out from the container;

(6) Calculate the volume of the remaining fine particles in step (3) according to formula ②. Obviously, this volume is the volume of the measured object v _{the measured object} ,

_{vMeasured object} = m ₂ /ρ _particle ②;

(7) Calculate the density ρ of the object to be _measured according to formula ③.

ρ _{measured object} = m _{measured object} /v _{measured object} ③.

Steps 1, 2, 4, 5 and 6 in the above content are the methods for measuring the volume of solid objects. Preferably, the particle size of the fine particles used in the method of the present invention is 20-40 mesh, which can make the particles fully contact and fill the surface of the object to be measured, which greatly improves the measurement accuracy.

Preferably, the fine particles used in the method of the present invention are grit and the container used is a glass container. Using glass material with less thermal deformation to prepare the container used in the present invention can make the measurement more accurate.

The present invention can satisfactorily solve the problems of volume and density measurement of solid objects with complex shapes, which are relatively difficult to solve in the prior art, and at the same time, has greater measurement accuracy.

Detailed ways

The present invention is explained with reference to the embodiments. The particles used in this example are quartz sand with a particle size of 20-40 meshes, and the container used is a glass cup with a volume of 326 ml and a mass of 110 grams.

Take a glass with a flat upper edge, the volume is 326 ml, and the mass is 110 grams. Select 20-40 mesh laboratory quartz sand, fill the glass, and use a ruler to level the upper edge of the glass. The mass of a glass filled with sand is 565.65 grams. Then according to formula ①, the density of quartz sand is calculated to be 1.398 g/cm3 (the bulk density of quartz sand). Leave 2 cm thick quartz sand at the bottom of the glass, transfer the rest of the quartz sand into a 250 ml beaker, put an irregular object in the glass, then fill the glass with quartz sand, and use a ruler on the top of the glass Scrape down. The mass of the remaining sand is 13.06 grams, then according to formula ②, the volume of quartz sand is calculated to be 9.34 cubic centimeters, which is equal to the volume of irregular objects. The mass of the irregular object is 13.09 grams when weighed on the balance, then the density of the object is calculated according to formula ③ to be 1.40 grams per cubic centimeter.

Claims (5)

1. A method for measuring the density of a solid object, characterized in that fine particles of uniform texture and a container having a mass m and a volume v are prepared in advance, and the measuring steps are as follows:

(1) the vessel is filled with fine particles and leveled with the upper edge of the vessel, and the fine particles and the total mass of the vessel are weighed and recorded as m₁；

(2) Calculating the density ρ of the fine particles in step (1) according to the formula ①_{Particulate matter}，

ρ_{Particulate matter}＝(m₁-m)/v₁①；

(3) Weighing and recording mass m of measured object_{Object to be measured}；

(4) Transferring part of fine particles out of the container for storage, only reserving the fine particles with the thickness of 2-3 cm at the bottom of the container, putting the solid matter to be measured into the container, enabling the highest position of the solid matter to be measured to be slightly lower than the upper edge of the container, filling the container with the fine particles transferred out of the container, and keeping the surface of the fine particles and the upper edge of the container to be flush;

(5) weighing and recording the mass m of the remaining fine particulate matter removed from the vessel₂；

(6) Calculating the volume v of the fine particles remaining from step (5) according to equation ②_{Object to be measured}，

v_{Object to be measured}＝m₂/ρ_{Particulate matter}②；

(7) Calculating the specific gravity rho of the object to be measured according to the formula ③_{Object to be measured}，

ρ_{Object to be measured}＝m_{Object to be measured}/v_{Object to be measured}③。

2. A method for measuring the volume of a solid object, characterized in that fine particles of uniform texture and a container of mass m and volume v are prepared beforehand, the measuring steps being as follows:

(1) the vessel is filled with fine particles and leveled with the upper edge of the vessel, and the fine particles and the total mass of the vessel are weighed and recorded as m₁；

(2) Calculating the density ρ of the fine particles in step (1) according to the formula ①_{Particulate matter}，

ρ_{Particulate matter}＝(m₁-m)/v₁①；

(3) Transferring part of fine particles out of the container for storage, only reserving the fine particles with the thickness of 2-3 cm at the bottom of the container, putting the solid matter to be measured into the container, enabling the highest position of the solid matter to be measured to be slightly lower than the upper edge of the container, filling the container with the fine particles transferred out of the container, and keeping the surface of the fine particles and the upper edge of the container to be flush;

(4) the remaining fine particles removed from the vessel and the total mass of the vessel were weighed and recorded as m₂；

(5) Calculating the volume v of the fine particles remaining from step (4) according to equation ②_{Object to be measured}，

v_{Object to be measured}＝m₂/ρ_{Particulate matter}②。

3. The method for measuring the density of a solid object according to claim 1 or the method for measuring the volume of a solid object according to claim 2, wherein the fine particulate matter has a particle size of 20 to 40 mesh.

4. A method according to claim 1 or 2 or 3, characterized in that the fine particles are gravel.

5. The method of claim 4 wherein said container is a glass container.