Question

A long rod of mass m, length l, cross-sectional area A
and Young's modulus y is suspended from one of its
ends. Then strain produced at a distance x from lower
end is
(1) mgx/Ayl
(2) mg//Ayx
(3) Ayxling
(4) mgyx/AI​

Answer 1

Explanation:

It seems pretty simple to solve

Your Answer is HERE

Answer 2

A long rod of mass m, length l, cross-sectional area A and Young's modulus y is suspended from one of its ends. Then strain produced at a distance x from lower end is  $\frac{mgx}{AyL}$

• In the given question, mass of rod at a point x from end is mass per unit length times x.
• Mass per unit length is given by $\frac{M}{L}$
• Young's modulas is given by$\frac{F}{A} \frac{dL}{L}$

• Strain is given by $\frac{dL}{L}$

Therefore,

              Y=  $\frac{xmg}{LA} \frac{1}{Strain}$

             Strain =  $\frac{mgx}{AyL}$