physics help?

Question

any little help would be great.

A steel beam 10m long is installed in a structure at 20 degrees Celsius. What are the beams changes in length at the temperature extremes of -30 degrees celsius to 45 degrees celsius

Answer 1

the thermal coefficient of linear expansion for iron or steel is
a=12x10E-6/K at 20 degrees C

So the change at -30 is 50 degrees
or 10*50*12x10E-6 m

and 45 is 25 degrees change
or 10*25*12x10E-6 m

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