Homework Help is Here – Start Your Trial Now!
Engineering
Mechanical Engineering
If lengths of rail track are laid down in cold weather, they may deform as they expand when the weather becomes warmer. Therefore, when rails are laid in cold weather they are stretched and fixed into place while still stretched. This is called pre-straining. The following data is typical for a length of steel rail: Young modulus of steel = 2.0 x 1011 Pa Cross sectional area of a length of rail = 7.5 x 10-3 m2 2.5 x 10-5 for each kelvin Amount of pre-strain = rise in temperature the rail is expected to experience. A steel rail is laid when the temperature is 8 °C and the engineer decides to use a pre-strain of 3.0 x 10-4. (a) Calculate the tensile force required to produce the pre-strain in the rail required by the engineer. (b) Calculate the elastic strain energy stored in a rail of unstressed length 45 m when pre-strained as in part (a) (c) Calculate the temperature at which the steel rail becomes unstressed.

If lengths of rail track are laid down in cold weather, they may deform as they expand when the weather becomes warmer. Therefore, when rails are laid in cold weather they are stretched and fixed into place while still stretched. This is called pre-straining. The following data is typical for a length of steel rail: Young modulus of steel = 2.0 x 1011 Pa Cross sectional area of a length of rail = 7.5 x 10-3 m2 2.5 x 10-5 for each kelvin Amount of pre-strain = rise in temperature the rail is expected to experience. A steel rail is laid when the temperature is 8 °C and the engineer decides to use a pre-strain of 3.0 x 10-4. (a) Calculate the tensile force required to produce the pre-strain in the rail required by the engineer. (b) Calculate the elastic strain energy stored in a rail of unstressed length 45 m when pre-strained as in part (a) (c) Calculate the temperature at which the steel rail becomes unstressed.

Elements Of Electromagnetics
Elements Of Electromagnetics
7th Edition
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Sadiku, Matthew N. O.
ChapterMA: Math Assessment
Section: Chapter Questions
Problem 1.1MA
See similar textbooks
icon
Related questions
Question

pleas 

QUESTION 4. If lengths of rail track are laid down in cold weather, they may deform as they expand when the weather becomes warmer. Therefore, when rails are laid in cold weather they are stretched and fixed into place while still stretched. This is called pre-straining. The following data is typical for a length of steel rail: Young modulus of steel = 2.0 x 101 Pa Cross sectional area of a length of rail = 7.5 x 10-3 m2 Amount of pre-strain = rise in temperature the rail is expected to experience. 2.5 x 10-5 for each kelvin A steel rail is laid when the temperature is 8 °C and the engineer decides to use a pre-strain of 3.0 x 104. (a) Calculate the tensile force required to produce the pre-strain in the rail required by the engineer. (b) Calculate the elastic strain energy stored in a rail of unstressed length 45 m when pre-strained as in part (a) (c) Calculate the temperature at which the steel rail becomes unstressed. (d) Explain why the engineer does not use the highest observed temperature at the location of the railway track to determine the amount of pre-strain to use.
Transcribed Image Text:QUESTION 4. If lengths of rail track are laid down in cold weather, they may deform as they expand when the weather becomes warmer. Therefore, when rails are laid in cold weather they are stretched and fixed into place while still stretched. This is called pre-straining. The following data is typical for a length of steel rail: Young modulus of steel = 2.0 x 101 Pa Cross sectional area of a length of rail = 7.5 x 10-3 m2 Amount of pre-strain = rise in temperature the rail is expected to experience. 2.5 x 10-5 for each kelvin A steel rail is laid when the temperature is 8 °C and the engineer decides to use a pre-strain of 3.0 x 104. (a) Calculate the tensile force required to produce the pre-strain in the rail required by the engineer. (b) Calculate the elastic strain energy stored in a rail of unstressed length 45 m when pre-strained as in part (a) (c) Calculate the temperature at which the steel rail becomes unstressed. (d) Explain why the engineer does not use the highest observed temperature at the location of the railway track to determine the amount of pre-strain to use.
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 3 steps with 3 images

SEE SOLUTIONCheck out a sample Q&A here
Blurred answer
Knowledge Booster
Slope and Deflection
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Elements Of Electromagnetics
Elements Of Electromagnetics
Mechanical Engineering
ISBN:
9780190698614
Author:
Sadiku, Matthew N. O.
Publisher:
Oxford University Press
Mechanics of Materials (10th Edition)
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:
9780134319650
Author:
Russell C. Hibbeler
Publisher:
PEARSON
Thermodynamics: An Engineering Approach
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:
9781259822674
Author:
Yunus A. Cengel Dr., Michael A. Boles
Publisher:
McGraw-Hill Education
Control Systems Engineering
Control Systems Engineering
Mechanical Engineering
ISBN:
9781118170519
Author:
Norman S. Nise
Publisher:
WILEY
Mechanics of Materials (MindTap Course List)
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:
9781337093347
Author:
Barry J. Goodno, James M. Gere
Publisher:
Cengage Learning
Engineering Mechanics: Statics
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:
9781118807330
Author:
James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:
WILEY
SEE MORE TEXTBOOKS