For each of the following pairs of polymers whether or not it is possible to decide whether one polymer has a higher tensile strength than the other; (2) if this is possible, note which has the higher tensile strength and then cite the reason(s) for your choice; and (3) if it is not possible to […]
For each of the following pairs of materials, decide which For each of the following pairs of materials, decide which has the larger thermal conductivity. Justify your choices. (a) Pure copper; aluminum bronze (95 wt% Cu-5 wt% Al). (b) Fused silica; quartz. (c) Linear polyethylene; branched polyethylene. (d) Random poly(styrene-butadiene) copolymer; alternating poly(styrene-butadiene) copolymer.
For both FCC and BCC crystal structures, there are two For both FCC and BCC crystal structures, there are two different types of interstitial sites. In each case, one site is larger than the other, and is normally occupied by impurity atoms. For FCC, this larger one is located at the center of each edge […]
For each of the following crystal structures, represent the indi For each of the following crystal structures, represent the indicated plane in the manner of Figures 3.11 and 3.12, showing both anions and cations: (100) plane for the rock salt crystal structure, (110) plane for the cesium chloride crystal structure, (111) plane for the zinc […]
The indices of refraction of fused silica and a soda–lime The indices of refraction of fused silica and a sodaâlime glass within the visible spectrum are 1.458 and 1.51, respectively. For each of these materials determine the fraction of the relative dielectric constant at 60 Hz that is due to electronic polarization, using the data […]
The lower yield point for an iron that has an The lower yield point for an iron that has an average grain diameter of 5 ( 10-2 mm is 135MPa (19,500psi). At a grain diameter of 8 ( 10-3 mm, the yield point increases to 260MPa (37,500psi). At what grain diameter will the lower yield […]
The permeability coefficient of a type of small gas molecule The permeability coefficient of a type of small gas molecule in a polymer is dependent on absolute temperature according to the following equation: where and Qp are constants for a given gas-polymer pair. Consider the diffusion of hydrogen through a poly (dimethyl siloxane) (PDMSO) sheet […]
The fraction of nonreflected radiation that is transmitted throu The fraction of nonreflected radiation that is transmitted through a 10-mm thickness of a transparent material is 0.90. If the thickness is increased to 20 mm, what fraction of light will be transmitted?
The index of refraction of corundum (Al2O3) is anisotropic. Supp The index of refraction of corundum (Al2O3) is anisotropic. Suppose that visible light is passing from one grain to another of different crystallographic orientation and at normal incidence to the grain boundary. Calculate the reflectivity at the boundary if the indices of refraction for the […]
The ends of a cylindrical rod 6.4 mm (0.25 in.) The ends of a cylindrical rod 6.4 mm (0.25 in.) in diameter and 250 mm (10 in.) long are mounted between rigid supports. The rod is stress free at room temperature [20(C (68(F)]; and upon cooling to -40(C (-40(F), a maximum thermally induced tensile stress […]