Four uniform wires of the same material are stretched by the same force. The dimensions of wire are as given below. The one which has the minimum elongation has
radius $3\ mm$, length $3\ m$
radius $0.5\ mm$, length $0.5\ m$
radins $2\ mm$, length $2\ m$
radius $3\ mm$, length $2\ m$
A wire of area of cross-section $10^{-6}\,m^2$ is increased in length by $0.1\%$. The tension produced is $1000\, N$. The Young's modulus of wire is
Two identical solid balls, one of ivory and the other of wet-clay are dropped from the same height on the floor. Which one will rise to a greater height after striking the floor and why ?
$A$ rod of length $1000\, mm$ and coefficient of linear expansion $a = 10^{-4}$ per degree is placed symmetrically between fixed walls separated by $1001\, mm$. The Young’s modulus of the rod is $10^{11} N/m^2$. If the temperature is increased by $20^o C$, then the stress developed in the rod is ........... $MPa$
A wire of length $L$ and radius $r$ is clamped at one end. If its other end is pulled by a force $F$, its length increases by $l$. If the radius of the wire and the applied force both are reduced to half of their original values keeping original length constant, the increase in length will become.
In steel, the Young's modulus and the strain at the breaking point are $2 \times {10^{11}}\,N{m^{ - 2}}$ and $0.15$ respectively. The stress at the breaking point for steel is therefore