An elevator cable can have a maximum stress of $7 \times 10^7\,N/m^2$ for appropriate safety factors. Its maximum upward acceleration is $1.5\,m/s^2$. If the cable has to support the total weight of $2000\,kg$ of a loaded elevator,the minimum area of cross-section of the cable should be ....... $cm^2$ $(g = 10\,m/s^2)$.

To break a wire,a breaking stress of $10^6 \, N/m^2$ is required. If the density of the material is $3 \times 10^3 \, kg/m^3$,then the length of the wire which will break by its own weight will be......... $m$ (Take $g = 10 \, m/s^2$)

$A$ wire of density $3 \times 10^3 \, kg/m^3$ requires a breaking stress of $10^6 \, N/m^2$ to break. What should be the length of the wire so that it breaks under its own weight? (Take $g = 10 \, m/s^2$)

In the given figure,two elastic rods $A$ and $B$ are rigidly joined to end supports. $A$ small mass $m$ is moving with velocity $v$ between the rods. All collisions are assumed to be elastic and the surface is frictionless. The time period of the small mass $m$ will be: [Here,an elastic rod may be treated as a spring of spring constant $k = \frac{YA}{L}$]

$A$ steel wire can sustain $100\,kg$ weight without breaking. If the wire is cut into two equal parts, each part can sustain a weight of ......... $kg$.

$Dyne/cm^2$ is not a unit of