Search results
Results From The WOW.Com Content Network
slug per cubic foot Imperial units differing from the above (as the Imperial gallon and bushel differ from the US units) in practice are rarely used, though found in older documents. The Imperial gallon was based on the concept that an Imperial fluid ounce of water would have a mass of one Avoirdupois ounce, and indeed 1 g/cm 3 ≈ 1.00224129 ...
The density of osmium is slightly greater than that of iridium; the two are so similar (22.587 versus 22.562 g/cm 3 at 20 °C) that each was at one time considered to be the densest element. Only in the 1990s were measurements made accurately enough (by means of X-ray crystallography) to be certain that osmium is the denser of the two. [11] [15]
The specific weight, also known as the unit weight (symbol γ, the Greek letter gamma), is a volume-specific quantity defined as the weight W divided by the volume V of a material: = / Equivalently, it may also be formulated as the product of density, ρ, and gravity acceleration, g: = Its unit of measurement in the International System of Units (SI) is newton per cubic metre (N/m 3), with ...
Concrete has a very low coefficient of thermal expansion, and as it matures concrete shrinks. All concrete structures will crack to some extent, due to shrinkage and tension. Concrete which is subjected to long-duration forces is prone to creep. The density of concrete varies, but is around 2,400 kilograms per cubic metre (150 lb/cu ft). [1]
For example, in the brewing industry, the Plato table lists sucrose concentration by weight against true SG, and was originally (20 °C/4 °C) [7] i.e. based on measurements of the density of sucrose solutions made at laboratory temperature (20 °C) but referenced to the density of water at 4 °C which is very close to the temperature at which ...
[citation needed] In the concrete and petroleum industry, however, a bag of cement is defined as 94 lb (43 kg) because it has an apparent volume close to 1 cubic foot (28 litres). [61] When ready-mix concrete is specified, a "bag mix" unit is used as if the batching company mixes 5 literal bags of cement per cubic yard (or cubic metre) when a ...
More water is therefore used than is chemically and physically necessary to react with cement. Water–cement ratios in the range of 0.40 to 0.60 are typically used. For higher-strength concrete, lower w/c ratios are necessary, along with a plasticizer to increase flowability.
Typically, a batch of concrete can be made by using 1 part Portland cement, 2 parts dry sand, 3 parts dry stone, 1/2 part water. The parts are in terms of weight – not volume. For example, 1-cubic-foot (0.028 m 3) of concrete would be made using 22 lb (10.0 kg) cement, 10 lb (4.5 kg) water, 41 lb (19 kg) dry sand, 70 lb (32 kg) dry stone (1/2 ...