Coefficient of linear expansion in a concrete slab

Question

Slabs of concrete used in highway construction are subject to expansion and contraction during temperature changes. Lab experiments have been performed to measure the expansion and contraction of a concrete slab 75.0 cm long and 25 cm wide. The slab is placed under ice at 0 degrees C until it is in thermal equilibrium with the ice; then it is sprayed with steam at 100 degrees C until it is in thermal equilibrium with the steam. A set of vernier apparatus are used to determine that the slab's width and length expand by an equal amount of 2.40 cm. Determine the coefficient of linear expansion of concrete from this data.

Thanks for any help! =)

Answer 1

the formula for the coefficient of the linear expansion is:

alpha=change in length/(original length*change in temperature)

as the slab is in thermal equilibrium so the change in temperature is 100 degrees C

to calculate the required quantity , i can consider any one of the length or breadth expansion.

the initial length is 75 cm and the change in length is given to be 2.40cm

so the calculation will give the coefficient of linear expansion to be 3.2multiplied10^-4