A bar is subjected to axial forces as shown. If $E$ is the modulus of elasticity of the bar and $A$ is its crosssection area. Its elongation will be
Diffcult
Download our app for free and get startedPlay store
(d)

Elongation in $I^{st}$ part

$\Delta x_1=\frac{\text { Net force } \times L}{A Y}$

$=\frac{(3+2) F L}{A E}$

$=\frac{5 F L}{A E}$

Elongation in $II^{nd}$ part

$\Delta x_2=\frac{(F-2 F) L}{A E}=-\frac{F L}{A E}$

So net elongation

$\Delta x=\Delta x_1+\Delta x_2$

$=\frac{5 F L}{A E}-\frac{F L}{A E}=\frac{4 F L}{A E}$

art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    A uniform wire of length $L$ and radius $r$ is twisted by an angle $\alpha$. If modulus of rigidity of the wire is $\eta$, then the elastic potential energy stored in wire, is $.........$
    View Solution
  • 2
    A vertical hanging bar of length $l$ and mass $m$ per unit length carries a load of mass $M$ at lower end, its upper end is clamped to a rigid support. The tensile stress a distance $x$ from support is $(A \rightarrow$ area of cross-section of bar)
    View Solution
  • 3
    A steel wire of length ' $L$ ' at $40^{\circ}\,C$ is suspended from the ceiling and then a mass ' $m$ ' is hung from its free end. The wire is cooled down from $40^{\circ}\,C$ to $30^{\circ}\,C$ to regain its original length ' $L$ '. The coefficient of linear thermal expansion of the steel is $10^{-5} { }^{\circ}\,C$, Young's modulus of steel is $10^{11}\, N /$ $m ^2$ and radius of the wire is $1\, mm$. Assume that $L \gg $ diameter of the wire. Then the value of ' $m$ ' in $kg$ is nearly
    View Solution
  • 4
    Choose the correct relationship between Poisson ratio $(\sigma)$. bulk modulus $( K )$ and modulus of rigidity $(\eta)$ of a given solid object:
    View Solution
  • 5
    For a given material, the Young's modulus is $2.4$ times that of rigidity modulus. Its Poisson's ratio is
    View Solution
  • 6
    If the interatomic spacing in a steel wire is $3.0Å$ and ${Y_{steel}}$= $20 \times {10^{10}}N/{m^2}$ then force constant is
    View Solution
  • 7
    Which of the following is true for elastic potential energy density
    View Solution
  • 8
    Young's modulus is determined by the equation given by $\mathrm{Y}=49000 \frac{\mathrm{m}}{\ell} \frac{\text { dyne }}{\mathrm{cm}^2}$ where $\mathrm{M}$ is the mass and $\ell$ is the extension of wre used in the experiment. Now error in Young modules $(\mathrm{Y})$ is estimated by taking data from $M-\ell$ plot in graph paper. The smallest scale divisions are $5 \mathrm{~g}$ and $0.02$ $\mathrm{cm}$ along load axis and extension axis respectively. If the value of $M$ and $\ell$ are $500 \mathrm{~g}$ and $2 \mathrm{~cm}$ respectively then percentage error of $\mathrm{Y}$ is :
    View Solution
  • 9
    The breaking stress of wire going over a smooth pully is $2 \times 10^9\, N/m^2$. What would be the minimum radius of wire used if it is not to break?
    View Solution
  • 10
    The isothermal bulk modulus of a gas at atmospheric pressure is
    View Solution