When a certain weight is suspended from a long uniform wire, its length increases by one $cm$. If the same weight is suspended from another wire of the same material and length but having a diameter half of the first one, the increase in length will be ......... $cm$
A$0.5$
B$2$
C$4$
D$8$
Medium
Download our app for free and get started
C$4$
c $\mathrm{y}=\frac{\mathrm{Fl}}{\alpha \Delta \mathrm{l}}$ or $\Delta \mathrm{l} \propto \frac{1}{\alpha} ; \Delta 1 \propto \frac{1}{\mathrm{D}^{2}}$
$\frac{\Delta \mathrm{l}_{2}}{\Delta \mathrm{l}_{1}}=\frac{\mathrm{D}_{1}^{2}}{\mathrm{D}_{2}^{2}}=4$ or $\Delta \mathrm{l}_{2}=4 \Delta \mathrm{l}_{1}=4 \mathrm{cm}$
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.*
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?
A steel wire is $1 \,m$ long and $1 \,mm ^2$ in area of cross$-$section. If it takes $200 \,N$ to stretch this wire by $1 \,mm$, how much force will be required to stretch a wire of the same material as well as diameter from its normal length of $10 \,m$ to a length of $1002 \,cm$ is $........ N$
The bulk modulus of a gas is defined as $B=-V d p / d V$. For an adiabatic process the variation of $B$ is proportional to $p^n$. For an ideal gas $n$ is
A bar of cross-sectional area $A$ is subjected two equal and opposite tensile forces at its ends as shown in figure. Consider a plane $BB'$ making an angle $\theta $ with the length The ratio of tensile stress to the shearing stress on the plane $BB'$ is
A rubber cord catapult has cross-sectional area $25\,m{m^2}$ and initial length of rubber cord is $10\,cm.$ It is stretched to $5\,cm.$ and then released to project a missile of mass $5gm.$ Taking ${Y_{rubber}} = 5 \times {10^8}N/{m^2}$ velocity of projected missile is ......... $ms^{-1}$
A wooden wheel of radius $R$ is made of two semicircular part (see figure). The two parts are held together by a ring made of a metal strip of cross section area $S$ and length $L$. $L$ is slighly less than $2\pi R$. To fit the ring on the wheel, it is heated so that its temperature rises by $\Delta T$ and it just steps over the wheel.As it cools down to surronding temperature, it presses the semicircular parts together. If the coefficint of linear expansion of the metal is $\alpha$, and its young's modulus is $Y$, the force that one part of wheel applies on the other part is