The problem with this idea is that there would be a significant sacrifice of stiffness, allowing, e.g., wings to flex unacceptably. Aluminum seems obvious because it is "lighter" than steel, but steel is stronger than aluminum, so one could imagine using thinner steel components to save weight without sacrificing (tensile) strength. To emphasize the point, consider the issue of choosing a material for building an airplane. Many common structures are stiffness-driven over much of their use, such as airplane wings, bridges, masts, and bicycle frames. The utility of specific modulus is to find materials which will produce structures with minimum weight, when the primary design limitation is deflection or physical deformation, rather than load at breaking-this is also known as a "stiffness-driven" structure. The dimensional analysis yields units of distance squared per time squared. High specific modulus materials find wide application in aerospace applications where minimum structural weight is required. It is also known as the stiffness to weight ratio or specific stiffness. Specific modulus is a materials property consisting of the elastic modulus per mass density of a material. June 1992.Ratio of stiffness to mass for a material Department of Energy, THERMODYNAMICS, HEAT TRANSFER, AND FLUID FLOW. DOE Fundamentals Handbook, Volume 1, 2 and 3. Fundamentals of Engineering Thermodynamics, Fifth Edition, John Wiley & Sons, 2006, ISBN: 978-7-0 Thermodynamics in Nuclear Power Plant Systems. Nuclear Systems Volume I: Thermal Hydraulic Fundamentals, Second Edition. Nuclear Reactor Engineering: Reactor Systems Engineering, Springer 4th edition, 1994, ISBN: 978-0412985317 Stacey, Nuclear Reactor Physics, John Wiley & Sons, 2001, ISBN: 0- 471-39127-1. Baratta, Introduction to Nuclear Engineering, 3d ed., Prentice-Hall, 2001, ISBN: 8-1. Lamarsh, Introduction to Nuclear Reactor Theory, 2nd ed., Addison-Wesley, Reading, MA (1983). It differs by about 9% and therefore ice floats on liquid water It has a maximum of density at 3.98 ☌ (1000 kg/m 3), whereas the density of ice is 917 kg/m 3. For example, water differs from most liquids in that it becomes less dense as it freezes. It must be noted, there are exceptions from this rule. Where ∆T is the change in temperature, V is the original volume, ∆V is the change in volume, and α V is the coefficient of volume expansion. The change in volume of a material which undergoes a temperature change is given by following relation: This phenomenon is known as thermal expansion. However, the amount of expansion or contraction varies, depending on the material. Most substances expand when heated and contract when cooled. The effect of temperature on the densities of liquids and solids is also very important. Compressibility is a measure of the relative volume change of a fluid or solid as a response to a pressure change. On the other hand, the density of gases is strongly affected by pressure. The effect of pressure on the densities of liquids and solids is very very small. Increasing the pressure always increases the density of a material. In general, density can be changed by changing either the pressure or the temperature.
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