The elastic limit of brass is 379 MPa . What should be the minimum diameter of a brass rod if it is to support a 400 N load without exceeding its elastic limit ?

Options

A. 1.00 mm
B. 0.90 mm
C. 1.36 mm
D. 1.16 mm

Answer

D

Explanation

Breaking stress `=(F)/(A)=(Fxx4)/(pid^(2))rArr(400xx4)/(pixxd^(2))=379xx10^(6)rArrd=1.16xx10^(-3)=1.16mm`