A load of 4.0 kg is suspended from a ceiling through a steel wire of radius 2.0 mm. Find the tensile stress developed in the wire when equilibrium is achieved. Take `g=3.1pi m/s^-2`

Explanation

tension in the wire is
`F=4.0x3.1piN`
`The area of cross section is
`A=pir^2=pix(2.0xx10^-2m)^2`
`=4.0pixx10^-6m^2`
Thus, the tensile stress developed.
`=F/A=(4.0xx3.1pi)/(4.0pixx10^-6)Nm^-2`
`=3.1xx10^6Nm^-2`