A metal wire is loaded beyond its elastic limit but before its breaking point.
Which statement is correct?
When the load is removed, the wire returns to its original unstretched length.
The wire has undergone plastic deformation, so it will have a permanent extension when the load is removed.
Hooke's law is still obeyed up to this point.
As the wire is stretched beyond its elastic limit, its diameter increases.
183 exam-style questions on CIE IGCSE Physics 1.5.1a Forces, resultant force and motion. Each one has a worked solution and a mark scheme showing where the marks go.