Answer :
Answer:
ν=0.308
Explanation:
Poisson's ratio can be found using not the elongations and contractions, but the strain of the material in the longitudinal and lateral directions.
In the given question, we can calculate axial strain εa as:
εa=(8.20312-8.2)/8.2=3.805*10^(-4) ft/ft
For the lateral strain, we can repeat calculations:
εl=(2.89966-2.9)/2.9=-1.172*10^(-4) in/in
Then, the Poisson's ratio ν can be found as:
ν=-εl/εa=-(-1.172*10^(-4))/(3.805*10^-4)=0.308
Note that negative sign means, that the deformations will have opposite directions and the final answer is positive for the coefficient.