New secrets of spider silk: exceptionally high thermal conductivity and its abnormal change under stretching

Xiaopeng Huang1, Guoqing Liu, Xinwei Wang

  • 1Department of Mechanical Engineering, Iowa State University, Ames, 50011, USA.

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San Francisco's Golden Gate Bridge is exposed to temperatures ranging from -15 °C to 40 °C. At its coldest, the main span of the bridge is 1275 m long. Assuming that the bridge is made entirely of steel, what is the change in its length between these temperatures?
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in temperature (ΔT) is 55 °C.
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