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A steel wire of density $8000\;kg/m^3$ weights $24\;gm$ and is $250\;cm$ long. It lengthens by $1.2\;mm$ when stretched by a force of $80\;N$. Calculate the Young's modulus for the steel and the energy stored in the wire.

Find the work done in stretching a wire of cross-sectional area $10^{-2}\;cm^2$ and $2\;m$ long through $0.1\;mm$, if $Y$ for the material of wires is $2\;*\;10^{11}\;N/m^2$.

How much force is required to punch a hole 1 cm in diameter in a steel sheet $5\;mm$ thick whose shearing strength is $2.76 \; * \; 10^8\;N/m^2$.

A vertical brass rod of the circular section is loaded by placing a $5\;kg$ weight on top of it. If its length is $50\;cm$ and radius of the cross-section is $1\;cm$, find the contraction of rod and the energy stored in it.

A uniform steel wire of density $7800\;kg/m^3$ weights $16\;gm$ and is $250\;cm$ long. It lengthens by $1.2\;mm$ when stretched by a force of $80\;N$. Calculate the Young's modulus and the energy stored in the wire.

A steel cable with a cross-sectional area $3\;cm^2$ has an elastic limit of $2.4\;*\;10^8\;pa$. Find the maximum upward acceleration that can be given a $1200\;kg$ elevator supported by the cable if the stress does not exceed one-third of the elastic limit.

Calculate the work done in stretching a steel wire $100\;cm$ in length and of cross-sectional area $0.03\;cm^2$ when a load of $100\;N$ is slowly applied before the elastic limit is reached.

What force is required to stretch a steel wire of cross-sectional area $1\;cm^2$ to double its length?

A uniform steel wire of density $8000\;kg\;m^{-3}$ weight $20\;gm$ and is $2.5\;m$ long. It lengthens by $1\;mm$ when stretched by a force of $80\;N$. Calculate the value of the Young's modulus of steel and the energy stored in the wire.