Q

# Help me answer: - Properties of bulk matter - NEET

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 wire is $'\Delta l'$ . Which of the following graphs is a straight line?

• Option 1)

$\Delta l \:versus\:\frac{1}{l}$

• Option 2)

$\Delta l \:versus\:l^{2}$

• Option 3)

$\Delta l \:versus\:\frac{1}{l^{2}}$

• Option 4)

$\Delta l \:versus\:l$

92 Views

As discussed in

Young Modulus -

Ratio of normal stress to longitudnal strain

it denoted by Y

$Y= \frac{Normal \: stress}{longitudnal\: strain}$

- wherein

$Y=\frac{F/A}{\Delta l/L}$

F -  applied force

A -  Area

$\Delta l$ -  Change in lenght

l - original length

$v = Al$

$Y = \frac{F/A}{\Delta l/l} = \frac{Fl}{A.\Delta L} \Rightarrow \Delta l = \frac{Fl}{YA}$

$\Delta l = \frac{Fl^{2}}{YV} \Rightarrow \Delta l \propto l^{2}$

Option 1)

$\Delta l \:versus\:\frac{1}{l}$

This solution is incorrect

Option 2)

$\Delta l \:versus\:l^{2}$

This solution is correct

Option 3)

$\Delta l \:versus\:\frac{1}{l^{2}}$

This solution is incorrect

Option 4)

$\Delta l \:versus\:l$

This solution is incorrect

Exams
Articles
Questions