Question

Three blocks a,b and c each of mass 4 kg are attached.both the wires are equal cross section area 5x 10^2 m^2. the surface is smooth. find the longitudinal strain in each wire if young modulus of both the wires is 2x10^11 n/m^2 (take g=10m/s^2)

Answer 1

Answer:

The value of each longitudinal strain of wire is 0.06 × $10^{-11}$ kg m $s^{-2}$

Explanation:

Given as :

The mass of each three block = 4 kg

So, Total mass of blocks = 3 × 4 kg = 12 kg

The cross section area = A = 500 square meter

The Young modulus = Y = 2 × $10^{11}$  n/m²

The value of g = 10  m/s²

Let The value of longitudinal strain = L

According to question

Young modulus = $\dfrac{\textrm Longitudinal stree}{longitudinal strain}$

Now, Longitudinal stress = $\dfrac{\textrm mass \times g}{Area}$

i.e Longitudinal stress = $\dfrac{\textrm 12 \times 10}{500}$

Or, Longitudinal stress = 0.24

∴  Longitudinal strain = $\dfrac{\textrm longitudinal stree}{\textrm young modulus}$

Or, L = $\dfrac{\textrm 0.24}{2\times 10^{11}}$

i.e L = 0.12 × $10^{-11}$

The value of longitudinal strain = L =  0.12 × $10^{-11}$

Or, The value of each longitudinal strain of wire = 0.06 × $10^{-11}$ kg m $s^{-2}$

Hence, The value of each longitudinal strain of wire is 0.06 × $10^{-11}$ kg m $s^{-2}$ Answer