The breaking stress for steel is` 8.0xx10^(2) Nm^(-2)` and its density is `8 xx 10^(2) "kgm"^(-3)`. The maximum length of a stee wire when can remain suspended without breaking is

Options

A. 1000 cm
B. 100 cm
C. 100cm
D. none

Answer

C

Explanation

Breaking stress = `(mg)/(A) = (rho(l_(max)Ag))/(A) = (l_(max) ) (rho) (g)`
`8 xx 10^(5) = l_(max). 8xx 10^(2) xx10:. l_(max) = (8xx10^(5))/(8xx 10^(3)):. l_(max) =100m`