Mechanical Properties of Solids - Result Question 4

5. Copper of fixed volume ’ V; is drawn into wire of length ’ l ‘. When this wire is subjected to a constant force ’ F ‘, the extension produced in the wi re is ’ Δl ‘. Which of the following graphs is a straight line?

[2014]

(a) Δl versus 1l

(b) Δl versus l2

(c) Δl versus 1l2

(d) Δl versus l

Show Answer

Solution:

  1. (b) As Y=FAΔllΔl=FlAY

But V=Al so A=Vl

Therefore Δl=Fl2VYl2

Hence graph of Δl versus l2 will give a straight line.



NCERT Chapter Video Solution

Dual Pane