What is the Maximum Load a Copper Wire Can Support?

[CaptFormal]

Homework Statement

(a) Copper has a breaking stress of about 3.00×108 N/m2. What is the maximum load that can be hung from a copper wire of diameter 0.37 mm?

(b) If 17 percent of this maximum load is hung from the copper wire, by what fraction of its original length will it stretch?

Homework Equations

The Attempt at a Solution

I know that this one is simple, I just can't find the correct formula to use. Anyone got any ideas?

 

[Q_Goest]

(a) They give you the diameter of the wire, so you have cross sectional area. You can also assume the wire is only in tension. Do you know how to calculate stress in a wire under tension?

(b) Given the load, can you find strain on this particular wire?