Help with srain on steels please

[bullvine]

Hi to all.
I am new on here and require some help on how to find out strain on a steel rod when all is known.
A 14mm rod carries a load of 3.08kn in tension.
i need to calculate the stress( this I know how to do) the answer is 20mpa.
The length is 2.5m,whats the strain? and find out the change in length. the E or elasticity is 200gpa.
I would appreciate your help
Cheers

 

[eeeeediot]

Well the formula for elasticity (a.k.a Young's Modulus) is E = stress / strain.

You already know E and you've calculated stress, so plug the numbers into the equation and find your strain.

If you want to go further, you can calculate the extension of the steel rod by using the formula for strain: Strain = (New Length - Original Length) / Original Length

Good luck with your studies.