The Young's modulus of a steel wire of length $6\,m$ and cross-sectional area $3\,mm ^2$, is $2 \times 11^{11}\,N / m ^2$. The wire is suspended from its support on a given planet. A block of mass $4\,kg$ is attached to the free end of the wire. The acceleration due to gravity on the planet is $\frac{1}{4}$ of its value on the earth. The elongation of wire is (Take $g$ on the earth $=10$ $\left.m / s ^2\right):$
JEE MAIN 2023, Medium
Download our app for free and get started
$\text { Tension }( F )= mg$
$=4 \times \frac{10}{4}=10\,N$
$\Delta L =\frac{ FL }{ AY }$
$=\frac{10 \times 6}{3 \times 10^{-6} \times 2 \times 10^{11}}$
$=10^{-4}\,m =0.1\,mm$
Download our appand 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
- 1The density and breaking stress of a wire are $6 \times$ $10^4 \mathrm{~kg} / \mathrm{m}^3$ and $1.2 \times 10^8 \mathrm{~N} / \mathrm{m}^2$ respectively. The wire is suspended from a rigid support on a planet where acceleration due to gravity is $\frac{1^{\text {rd }}}{3}$ of the value on the surface of earth. The maximum length of the wire with breaking is ............ $\mathrm{m}$ (take, $\mathrm{g}=$ $\left.10 \mathrm{~m} / \mathrm{s}^2\right)$View Solution
- 2A uniform wire (Young's modulus $2 \times 10^{11}\, Nm^{-2}$ ) is subjected to longitudinal tensile stress of $5 \times 10^7\,Nm^{-2}$ . If the over all volume change in the wire is $0.02\%,$ the fractional decrease in the radius of the wire is close toView Solution
- 3When a rubber ball is taken to the bottom of a sea of depth $1400 \,m$, its volume decreases by $2 \%$. The Bulk modulus of rubber ball is .................. $\times 10^8 N / m ^2$ [density of water is $1 \,g cc$ and $g=10 \,m / s ^2$ ]View Solution
- 4The ratio of lengths of two rods $A$ and $B$ of same material is $1 : 2$ and the ratio of their radii is $2 : 1$, then the ratio of modulus of rigidity of $A$ and $B$ will beView Solution
- 5View SolutionThe longitudinal strain is only possible in
- 6One end of a metal wire is fixed to a ceiling and a load of $2 \mathrm{~kg}$ hangs from the other end. A similar wire is attached to the bottom of the load and another load of $1 \mathrm{~kg}$ hangs from this lower wire. Then the ratio of longitudinal strain of upper wire to that of the lower wire will be____________.View Solution
[Area of cross section of wire $=0.005 \mathrm{~cm}^2$, $\mathrm{Y}=2 \times 10^{11}\ \mathrm{Nm}^{-2}$ and $\left.\mathrm{g}=10 \mathrm{~ms}^{-2}\right]$
- 7A wire of length $L$ and radius $r$ is clamped rigidly at one end. When the other end of the wire is pulled by a force $f$, its length increases by $l$. Another wire of same material of length $2 L$ and radius $2 r$ is pulled by a force $2 f$. Then the increase in its length will beView Solution
- 8If the Young's modulus of the material is $3$ times its modulus of rigidity, then its volume elasticity will beView Solution
- 9When a force is applied on a wire of uniform cross-sectional area $3 \times {10^{ - 6}}\,{m^2}$ and length $4m$, the increase in length is $1\, mm.$ Energy stored in it will be $(Y = 2 \times {10^{11}}\,N/{m^2})$View Solution
- 10The elastic behaviour of material for linear streass and linear strain, is shown in the figure. The energy density for a linear strain of $5 \times 10^{-4}$ is $\dots \; kJ / m ^{3}$. Assume that material is elastic upto the linear strain of $5 \times 10^{-4}$.View Solution
