Principles Giancoli
Physics: with Applications, 6th Edition
(c) For concrete, repeat the calculation with the expansion coefficient and elastic modulus for concrete.
Stress FA ET 12 10
6
Co
20 109 N m2
60 C o
1.4 107 N m2
6 2 The ultimate tensile strength of concrete is 2 10 N m , and so the concrete will fracture .
25. (a) Calculate the change in temperature needed to increase the diameter of the iron band so that it fits over the barrel. Assume that the barrel does not change in dimensions. L L0 T L L0 L0 T T0
T
T0
L L0 L0
20o C
134.122 cm 134.110 cm 12 10
6
C
o
134.110 cm
27.457 o C
27 o C
(b) Since the band cannot shrink while cooling, the thermal stress must compensate in order to keep the length at a constant 132.122 cm. E is Youngs modulus for the material. L Stress F A ET F AE AE T L0
7.4 10 2 m 6.5 10 3 m 100 109 N m 2 12 10
6
Co
32
7.457Co
273.15 .
4.3 103 N
26. Use the relationships T K ) (a T K (b ) T K (c) T K (d ) T K (e) T K
T
o
C
273.15 and T K 359 K
273.15
5 9
T
o
F
T
5 9
o
C
o
273.15 86 273.15
F 32 273.15
5 9
T
o
78 32
299 K
T T
5 9
C C
o
273.15
100 273.15
173 K 5773 K
273.15 0.37 K
o
273.15 5500 273.15
F 32 273.15
5 9 5 9
T
459 32 32
27. Use the relationship that T K
T
o
F
273.15 .
TK T
o
5 9 9 5
T
o
F
32
273.15 32
9 5
F
TK
273.15
0 273.15
o
32
459.67o F
28. Use the relationship that T K (a ) T K (b) % error
T
C
273.15 . 4300 K ; T K
T
o
T
o
C
T
273.15
100
100
4270 K
273 100
C
273.15
15 106 K
TK
273 4000
TK
7%
4000o C:
15 106 o C:
273 15 10
6
100
2 10 3%
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