74 



Tables 47-47a. 

 ELASTIC MODULI. 



TABLE 47. — Rigidity Modnlns. 



If to the four consecutive faces of a cube a tangential stress is applied, opposite in direction on 

 adjacent sides, the modulus of rigidity is obtained by dividing the numerical value of the tangential 

 stress per unit area (kg. per sq. mm.) by the number representing the change of angles on the 

 non-stressed faces, measured in radians. 



Substance. 



Aluminum 



" cast .... 

 Brass 



" cast, 6oCu+ i2Sn , 

 Bismuth, slowly cooled . , 

 Bronze, cast, 88 Cu + 1 2 Sn 

 Cadmium, cast . . . . . 

 Copper, cast 



« 

 Gold. ..'.'.'.'.'. 



Iron, cast 



« 



« 



it 



Magnesium, cast . . . , 



Nickel 



Phosphor bronze . . . , 



Rigidity 

 Modulus. 



3350 

 2580 



3550 

 3715 

 3700 

 1240 

 4060 

 2450 

 4780 

 4213 

 4450 

 4664 

 2850 



3950 

 5210 

 6706 



7975 

 6940 

 8108 



7505 

 1710 

 7820 

 4359 



Refer- 



14 



5 



10 



II 



5 

 5 

 5 

 5 



19 



5 



14 



5 



IS 

 10 



7 

 16 



14 

 5 

 5 



II 



Substance. 



Quartz fibre . . . 

 Silver 



" hard-drawn . 

 Steel 



" cast . , . . 



'* cast, coarse gr. 



" silver- . . . 

 Tin, cast . . . . 



Zinc 



Platinum . . . . 



Glass 



Clay rock . . . . 



Granite 



Marble 



Slate 



Rigidity 

 Modulus. 



2380 

 2960 

 2650 

 2566 

 2816 

 8290 



7458 

 8070 

 7872 

 1730 

 1543 

 3880 

 3820 

 6630 

 6220 



2350 

 2730 

 1770 

 1280 

 1190 

 2290 



Refer- 

 ence. 



20 

 21 



5 



10 

 16 

 II 

 16 

 15 



5 

 II 



5 

 19 



5 



19 

 16 



23 

 23 

 23 

 23 



References 1-16, see Table 48. 



17 Gratz, Wied. Ann. 28, 1886. 



18 Savart, Pogg. Ann. 16, 1829. 



19 Kievviet, Diss. Gottingen, 1886. 



20 Threlfall, Philos. Mag. (5) 30, i{ 



21 Boys, Philos. Mag. (5) 30, 1890. 



22 Thomson, Lord Kelvin. 



23 Gray and Milne. 



24 Adams-Coker, Carnegie Publ. No. 46, 



1906. 



TABLE 47a. —Variation of tlie Rigidity Modnlns with tbe Temperatnre. 



ftt^Mo {i — of — Pf^ — 7/^), where / = temperature Centigrade. 



Substance. 



Brass . 

 If 



Copper . 



Iron . . 



Platinum 

 Silver . 

 Steel . 



PiqS 



Authority. 



Pisati, Nuovo Cimento, 5, 34, 1879. 



Kohlrausch-Loomis, Pogg. Ann. 141. 



Pisati, loc. cit. 



K and L, loc. cit. 



Pisati, loc. cit. 



K and L, loc. cit. 



Pisati, loc. cit. 



«<* = «,5 [i — a(/ — 15)]; Horton, Philos, Trans. 204 A, 1905. 



o =.00039 



.00038 

 .00029 

 .00026 



: .00012 

 .00031 

 .00048 

 .00148 



o = .oo4i6 

 .00164 

 .0058 

 .00012 



Smithsonian Tables. 



* Modulus of rigidity in 10^* dynes per sq. cm. 



