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pychu [463]
4 years ago
5

Why do most sidewalks have cracks in them every few feet?

Chemistry
2 answers:
Licemer1 [7]4 years ago
8 0
This is actually a really good question! The lines are actually called "contraction joints." When the sidewalk is being made, the concrete used shrinks as it dries. This shrinking can cause cracks to form in the sidewalk, so to prevent the cracks from forming randomly, the builders make thin lines. Any cracks that form should follow the path of the line, since this is where the concrete is thinnest.

Hope this helps! :)
Elodia [21]4 years ago
7 0
It's because of the landscape, it changes over time.
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Answer:

143 parts I think probably not

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What is the acceleration of an object if it goes from a velocity of +25m/s to rest in 5.0s?
kari74 [83]

Vf = Vi + at

0 m/s = 25 m/s + a(5sec)

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Have people considered that aliens could possibly live without oxygen and water and we are looking in the wrong direction for a
bija089 [108]
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3 years ago
Why is it important for a scientist studying greenhouse effect to know about mater,forces and energy
vova2212 [387]
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3 years ago
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Nady [450]

Answer:

0.825 M

Explanation:

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3 years ago
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