If the density ratio of a and B is 3:1 and their volume ratio is 3:2, then their mass ratio is 3:1______ ．

If the density ratio of a and B is 3:1 and their volume ratio is 3:2, then their mass ratio is 3:1______ ．

From ρ = MV, we get m a m B & nbsp; = ρ a × v a ρ B × v b = 31 × 32 = 92

If the density ratio of a and B is 3:1 and their volume ratio is 2:3, what is their mass ratio?
It's better to say that the next process does not want as long as the answer that

Let the density of a be 3x, then the density of B be x; the volume of a be 2Y, then the volume of B be 3Y; the mass of a be 3x * 2Y = 6xy; the mass of B be x * 3Y = 3xy. Their mass ratio is 6xy / 3xy = 2, that is 2:1

The mass of a metal block is 81g, and the volume is 30 cubic centimeter. To find the density of the metal block, I need the answer immediately

81 / 30 = 2.7g/cm3
aluminium

Four cubes with the same edge length are put together to form a cuboid, and the surface area is reduced by 90 square decimeters?

The area of one face of the original cube
90 / 6 = 15 square decimeters
The surface area of a cuboid
5x15x2+4x15x2=270

How to calibrate the standard sand density in sand filling method? According to the specification, the density should be 1.47 ~ 1.61g/cm3. How much is this?

The precision value is measured by ourselves. Who can prepare the sand with specific density for us? Take the container with known volume, pour the sand, adjust the compactness to meet the requirements of calibration, and measure it several times, then take the average value

How to understand the density formula: density = mass / time?

Understand the formula of density: 1. The physical quantities involved in the formula ρ = m / V are all for the same object, so we must not wear such a hat. Generally, the international system of units should be used for calculation. If the common unit is used, the unit of mass is g, and the unit of volume is cm ^ 3, then the unit of density should be g / cm3; 2. For the same material or

What is the definition of density? What is the formula of density?

The mass of an object per unit volume. Mass divided by volume

What are the main factors that affect the measurement results of stone bulk density?

The main factors are the stacking method, such as whether the tamping is the tamping table or the manual tamping, the bumping strength, etc. the tamping depends on the operation method, the time interval, the height control of the tamping rod falling, etc. the loose square density is mainly the standard degree of the loading, and the other main factor is the calibration of the volume and the temperature during the test

What is the approximate density of sand?

Generally no more than 2.54 g / cm

What is the unit of energy flux density? Give an example

Energy / unit time * unit area (J / m ^ 2 * s)