Question

A thin mild steel wire is loaded by adding loads in equal increments till it breaks. The extensions noted with increasing loads will behave as under:-

• A. uniform throughout
• B. increase uniformly
• C. first increase and then decrease
• D. increase uniformly first and then increase rapidly

Answer 1

Answer:

D. increase uniformly first and then increase rapidly

As the mild steel wire is loaded in equal increments till it breaks, the extensions noted with increasing loads will increase uniformly first and then increase rapidly. This is because, after the yield load, further increase in load will cause marked deformation in the whole volume of the metal, leading to a rapid increase in extension. The maximum load which the specimen can withstand without failure is called the load at the ultimate strength.