Tensile Strength and Solution
problem 261
A steel rod with a cross-sectional area of 0.25 in2 is stretched between two fixed points. The tensile load at 70°F is 1200 lb. What will be the stress at 0°F? At what temperature will the stress be zero? Assume α = 6.5 × 10-6 in/(in·°F) and E = 29 × 106 psi. Solution 261
For the stress at 0°C:
answer For the temperature that causes zero stress:
answer problem 262
A steel rod is stretched between two rigid walls and carries a tensile load of 5000 N at 20°C. If the allowable stress is not to exceed 130 MPa at -20°C, what is the minimum diameter of the rod? Assume α = 11.7 µm/(m·°C) and E = 200 GPa. Solution 262
d answer Problem 263
Steel railroad reels 10 m long are laid with a clearance of 3 mm at a temperature of 15°C. At what temperature will the rails just touch? What stress would be induced in the rails at that temperature if there were no initial clearance? Assume α = 11.7µm/(m·°C) and E = 200 GPa. Solution 263
Temperature at which :
answer Required stress:
answer
Problem 264
A steel rod 3 feet long with a cross-sectional area of 0.25 in.2 is stretched between two fixed points. The tensile force is 1200 lb at 40°F. Using E = 29 × 106 psi and α= 6.5 × 10-6 in./(in.·°F), calculate (a) the temperature at which the stress in the bar will be 10 ksi; and (b) the temperature at which the stress will be zero. Solution 264
(a) Without temperature change:
A drop of temperature is needed to increase the stress to 10 ksi. See figure above.
Required temperature: (temperature must drop from 40°F) answer (b) From the figure below:
answer th a cross sectional area of 320 mm2 is placed between two rigid walls as shown in Fig. P-265. At a temperature of -20°C, the gap Δ = 25 mm. Find the temperature at which the compressive stress in the bar will be 35 MPa. Use α = 18.0 × 10-6 m/(m·°C) and E = 80 GPa. Problem 265
answer Problem 266
Calculate the increase in
A steel rod with a cross-sectional area of 0.25 in2 is stretched between two fixed points. The tensile load at 70°F is 1200 lb. What will be the stress at 0°F? At what temperature will the stress be zero? Assume α = 6.5 × 10-6 in/(in·°F) and E = 29 × 106 psi. Solution 261
For the stress at 0°C:
answer For the temperature that causes zero stress:
answer problem 262
A steel rod is stretched between two rigid walls and carries a tensile load of 5000 N at 20°C. If the allowable stress is not to exceed 130 MPa at -20°C, what is the minimum diameter of the rod? Assume α = 11.7 µm/(m·°C) and E = 200 GPa. Solution 262
d answer Problem 263
Steel railroad reels 10 m long are laid with a clearance of 3 mm at a temperature of 15°C. At what temperature will the rails just touch? What stress would be induced in the rails at that temperature if there were no initial clearance? Assume α = 11.7µm/(m·°C) and E = 200 GPa. Solution 263
Temperature at which :
answer Required stress:
answer
Problem 264
A steel rod 3 feet long with a cross-sectional area of 0.25 in.2 is stretched between two fixed points. The tensile force is 1200 lb at 40°F. Using E = 29 × 106 psi and α= 6.5 × 10-6 in./(in.·°F), calculate (a) the temperature at which the stress in the bar will be 10 ksi; and (b) the temperature at which the stress will be zero. Solution 264
(a) Without temperature change:
A drop of temperature is needed to increase the stress to 10 ksi. See figure above.
Required temperature: (temperature must drop from 40°F) answer (b) From the figure below:
answer th a cross sectional area of 320 mm2 is placed between two rigid walls as shown in Fig. P-265. At a temperature of -20°C, the gap Δ = 25 mm. Find the temperature at which the compressive stress in the bar will be 35 MPa. Use α = 18.0 × 10-6 m/(m·°C) and E = 80 GPa. Problem 265
answer Problem 266
Calculate the increase in