A metal wire of length $L_1$ and area of cross section $A$ is attached to a rigid support. Another metal wire of length $L_2$ and of the same cross sectional area is attached to the free end of the first wire. A body of mass $M$ is then suspended from the free end of the second wire. If $Y_1$ and $Y_2$ are the Youngs moduli of the wires respectively, the effective force constant of the system of two wires is :
$\frac{{\left[ {\left( {{Y_1}{Y_2}} \right)A} \right]}}{{\left[ {2\left( {{Y_1}{L_2} + {Y_2}{L_1}} \right)} \right]}}$
$\frac{{\left[ {\left( {{Y_1}{Y_2}} \right)A} \right]}}{{{{\left( {{L_1} + {L_2}} \right)}^{\frac{1}{2}}}}}$
$\frac{{\left[ {\left( {{Y_1}{Y_2}} \right)A} \right]}}{{\left[ {\left( {{Y_1}{L_2} + {Y_2}{L_1}} \right)} \right]}}$
$\frac{{\left[ {{{\left( {{Y_1}{Y_2}} \right)}^{1/2}}A} \right]}}{{{{\left( {{L_1} + {L_2}} \right)}^{1/2}}}}$
A 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 the same material of length $2L$ and radius $2r$ is pulled by a force $2f$. Then find the increase in length of this wire.
A fixed volume of iron is drawn into a wire of length $L.$ The extension $x$ produced in this wire by a constant force $F$ is proportional to
What is the percentage increase in length of a wire of diameter $2.5 \,mm$, stretched by a force of $100 \,kg$ wt is .................. $\%$ ( Young's modulus of elasticity of wire $=12.5 \times 10^{11} \,dyne / cm ^2$ )
Two steel wires of same length but radii $r$ and $2r$ are connected together end to end and tied to a wall as shown. The force stretches the combination by $10\ mm$. How far does the midpoint $A$ move ............ $mm$
Young’s modulus of perfectly rigid body material is