An aluminum wing on a passenger jet is 32 m long when its temperature is 27°C. At what temperature would the wing be 2 cm (0.02 m) shorter?

Question

An aluminum wing on a passenger jet is 32 m

long when its temperature is 27°C.

At what temperature would the wing be 2 cm (0.02 m) shorter?

Answer 1

This is a problem in thermal expansion/contraction.

The change in length is given by: dL = alpha * L * dT

alpha is the thermal expansion coefficient of aluminum, found in a table in your textbook

L = 32m (the original length)

dL = -0.02m (contraction by 2cm)

Calculate the change in temperature dT from the equation. It will be negative, just like dL.

The required temperature will be below 27C: T = 27C + dT