Question

The breaking stress of aluminium is 7.5 into 10 to the power 7 newton per metre square find the greatest length of aluminium wire that can hang vertically without breaking density of aluminium is 2.7 into 10 to the power 3 kg per metre cube

Answer 1

Answer:

Breaking stress of  = σ=7.5x 10⁷ N/m2

density of Aluminium= ρ =2.7 X 103 kg/m3

g=10m/s²

let the maximum length that can be hung vertically be L

 Let CSA=A

volume of wire=AL

mass of wire=ρAL

when hung force acting on the wire

F=ρALg

F/A=ρlg

 σ= ρlg

now maximum, stress that wire can withstand σ=σb

so,

ρLg=σb  =7.5x 10⁷

L=7.5x 10⁷/ρg

=7.5x 10⁷/2.7x10³x10

L=2.77x10³ m