Linear expansion by heat for an object

[ehf]

Homework Statement

http://i.imgur.com/swYr8aw.jpg

Homework Equations

delta L=LalphadeltaT

The Attempt at a Solution

sorry for s**ty handwriting look at #8[/B]

http://i.imgur.com/59Ew8vJ.jpg

edit:click the links please. The forum software cropped the quality of the photo.

 

[haruspex]

I cannot read the problem statement. If I blow it up large enough to be read it is just a blur.

 

[ehf]

I cannot read the problem statement. If I blow it up large enough to be read it is just a blur.

fixed problem

 

[haruspex]

fixed problem

The linked image is hardly any better. Why not take a closer shot instead of leaving all that whitespace?

 

[Nidum]

That's the best I can do with computer enhancement .

I could not do much with the other image .

 

[haruspex]

View attachment 204449

That's the best I can do with computer enhancement .

I could not do much with the other image .

Much better. I concur with both answers.

 

[ehf]

Much better. I concur with both answers.

View attachment 204449

That's the best I can do with computer enhancement .

I could not do much with the other image .

The imgur link should be just fine. I can read it on all magnification. The server cropped the displaying image whatever i did

 

[Nidum]

@ehf . We understand the question now .

This type of problem comes up frequently and once you understand one simple principle solving these problems becomes easy and usually requires little calculation .

Consider a square plate with a round hole in it - do you think that the hole gets larger or smaller in diameter when the plate is heated ?

 

[ehf]

smaller because of expansion @Nidum
(i have an exam coming up so i may not access frequently...)

 

[haruspex]

Consider a square plate with a round hole in it - do you think that the hole gets larger or smaller in diameter when the plate is heated ?

smaller

I must be missing something.
My reading of the answer to a) at the link, messy as it is, is that the gap increases, which is correct.
@Nidum's post #8 implies that at some point in @ehf's posts it is stated that the gap will shrink, but I cannot find such.
In response to the direct question from Nidum, ehf says that a gap would shrink.
@Nidum, what made you suspect ehf would answer wrongly?

 

[Nidum]

I was working towards explaining the basic physics of expansion . In particular that gaps expand in the same way as solid metal .

I was still having difficulty reading ehf's writing when I made that posting .

 

[ehf]

my fault...it doesn't shrink anywhere...only stretches
well please do not use the image on the thread. imgur images are almost megabytes while the images on the forum are kilobytes
im sorry i can't convert it to text now