There are very many equations which depend on what information you have been given.
If you know the density of the rectangular body you can find the volume and the plug it into this equation mass= (density)*(volume) If you have the means you can just submerge the body completely in water and find the volume of the water displaced that will be the mass as waters density is 1 g/cm^3
The equation to find the volume of a rectangular object is (a) volume equals length times width times height.
Volume = Length * Width * Height
the three dimensions needed to find the area of a rectangular solid object are: Height, Length and Width.
If it is a cube (basically a square) or a rectangular prism multiply the top, the length, and the base.
Volume of any prism = cross-section area times length
A rectangular prism has a volume that can be found by multiplying the object's length width and height. To obtain the mass one must also know the density of the object and multiply that by the volume.
length, width and height (:
Height x Weight x Height
Height x Weight x Height
Height x Weight x Height
To find the density of a rectangular solid object, you would calculate the mass of the object by multiplying its volume by its density. For an irregular solid object, you would typically measure its mass using a balance and its volume using displacement of water, then divide the mass by the volume to find the density. The main difference lies in how you determine the volume of the object, with rectangular solids having a straightforward formula for volume calculation compared to irregular shapes which require more complex methods.