A) Steel train rails are laid in 12.6m -long segments placed end to end. The rails are laid on a winter day when their temperature is -2.00C. How much space must be left between adjacent rails if they are just to touch on a summer day when their temperature is 30.5C?
(in mm)
B) If the rails are mistakenly laid in contact with each other, what is the stress in them on a summer day when their temperature is 30.5?
(Pa)