A material breaks up under a stress of `20xx10^(5)N//m^(2)`. If the density of the material is `2.5xx10^(3)kg//m^(3)`, calculate the length may break under its own weight.(Take `g=10m//s^(2)`)

Explanation

Let L, A and `rho` be lengt, area of cross section and density of the material of the wire. W is the weight of the wire. The stress due to this weight.
`(W)/(A)=Lrhog`
The breaking stress is,
`thereforeLrhog=20xx10^(5)N//m^(2)`
(or) `L=(20xx10^5)/(2.5xx10^(3)xx10)=(200)/(2.5)`
`=80` metres