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Acceleration due to gravity

surface of a massive body, such as a planet. Also known as the acceleration of free fall, its value can be calculated from the formula g = GM / (R + h) 2 whereM is the mass of the gravitating body (such as the Earth), R is the radius of the body, h is the height above the surface, and G is the gravitational constant (= 6.6742 × 10-11 N·m2/kg2). If the falling object is at, or very nearly at, the surface of the gravitating body, then the above equation reduces to g = GM / R 2 In the case of the Earth, g comes out to be approximately 9.8 m/s2(32 ft/s2), though the exact value depends on location because of two main factors: the Earth's rotation and the Earth's equatorial bulge. The earth is not perfectly round, it is slightly egg-shaped, wider at the equator as it spins. The farther you are from the center of the earth the less gravity, the less you weigh. So if you are on a high mountain or at the equator you...

Role of FM of sand

The grading and maximum size of aggregates is important parameters in any concrete mix. They affect relative proportions in mix, workability, economy, porosity and shrinkage of concrete etc. Experience has shown that very fine sands or very coarse sands are objectionable – the former is uneconomical, the latter gives harsh unworkable mixes. Thus the object in this paper is to find the best fineness modulus of sand to get the optimum grading of combined aggregate (all-in-aggregate), which is most suitable, and for economy. In general, the grading of aggregates, which do not have a deficiency or excess of any size of aggregate and give a smooth grading curve, produce the most suitable concrete mix. Further a cohesive mix is also desired for the pumped concrete produced by RMC Plant. In the present investigations, effect of the grading of river sand particles has been investigated for a good Concrete mix. Sand has been sorted in three categories i.e. Fine, Medium, and Coarse. These w...