- #1

- 11

- 0

a) The sample of copper wire reached its elastic limit when the stress is 1.4x10^8 Pa and the strain is 0.035 Calculate the Young's Modulus for copper.

My attempt is Y= Stress/Strain => Y= 140000000/0.035 => 4,000,000,000 => 4x10^9

Hope this part is correct

b) What tensil force would be needed to reach the elastic limit of the copper wire of cross sectional area 1mm sq

F = Force A= Area e= extention Y= Young's Modulus l = lenght

My attempt is F= (A x e x Y) / l => F= (0.001 x 0.035 x 4,000,000,000) / 1 => 140,000 => 1.4x10^5

I took my length as 1m and extention was 0.035m from the original strain = 0.035

not sure if I am right as I have no contact with my lecturures until my exam I ask if somebody could tell me if my work is right or wrong and where I have gone wrong if so

Thx Paul