What are the Reasons for the Experiment Set-Up in Measuring Young's Modulus?

[Hardik Batra]

Question 1:

--> Why both the wires are suspended from the same rigid support in this experiment?

Question 2:

-->Why both the wires are taken of the same material?

 

[SteamKing]

Question 3:

--> Why do you think any of us know what you are talking about?

 

[Emilyjoint]

I think I know because this is a standard set up to find Young's modulus.
One of the wires is a reference wire which reduces errors due to changes in temperature.
The reference wire and the test wire are connected to the same support to reduce errors due to yielding of the support when the test wire is loaded.
Extension is measured using a vernier scale.