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Linear expansion of solid

  • Thread starter chawki
  • Start date
  • #1
510
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Homework Statement


A girder made of steel. The length of the girder is 3.77 m. In the middle of the girder there is a fracture. The temperature rises 32° C.

Homework Equations


Find the height that the girder rises from the middle, if it is fixed at both ends. The linear expansion coefficient for steel is 12*10^-6 /C.


The Attempt at a Solution


Is it 1.79m?
 

Answers and Replies

  • #2
gneill
Mentor
20,793
2,773

The Attempt at a Solution


Is it 1.79m?
Seems a bit unlikely. Show your work.
 
  • #3
510
0
L-L0 = 1.2 E-5 * 3.77 * 32 = 0.00144m
L=3.77+0.00144 = 3.77144

3.77144/2= 1.88572
3.77/2= 1.885

1.885722 =x2 + 1.8852
x=0.052m ?
 

Attachments

  • #4
gneill
Mentor
20,793
2,773
That looks better!
 
  • #5
510
0
Wow, my answer is correct?!
 
  • #6
gneill
Mentor
20,793
2,773
You sound surprised.:smile:
 
  • #7
510
0
yes iam. i lost some self-confidence
 
  • #8
510
0
You sound surprised.:smile:
I think it doesn't look correct...because the the difference between L and L0 is tooooo small to allow the use Pythagorean theorem, don't you think ?
 
  • #9
gneill
Mentor
20,793
2,773
I don't know of any reason why Pythagoras would fail to work no matter how small the difference was; a triangle is still a triangle if it has three sides!
 

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