The breaking stress for a metal is 7.8 xx 10^9 Nm^-2. Calculate the maximum length of the wire of this metal which may be suspended breaking. The density of the metal =7.8 xx 10^3kg m^-3. Take g =10 N kg^-1

The breaking stress for a metal is 7.8 xx 10^9 Nm^-2. Calculate the ma

1.	The breaking stress for a metal is 7.8 xx 10^9 Nm^-2. Calculate the maximum length of the wire of this metal which may be suspended breaking. The density of the metal =7.8 xx 10^3kg m^-3. Take g =10 N kg^-1
Answer» Solution :BREAKING stress = Maximum stress that the wire can withstand = `7.8 xx 10^(9) Nm^(–2)` When the wire is suspended vertically, it tends to break under its own weight. LET its length be I and cross-sectional area A. Weight of wire = mg = VOLUME `xx` density `xx` g = `Alrho`g Stress=` ("Weight")/(A)= Alrhog//A=lrhog` For the wire not to break, `lrho` g = Breaking stress = `7.8 xx 10^(9) Nm^(–2)` `:. "" l=(7.8xx10^(9))/(rhog)=(7.8xx10^(9))/(7.8xx10^(3)xx10)=10^(5)`m.