Q.

A massless uniform rod is subjected to force F at its free end as shown in figure. The ratio of tensile stress at plane P1 to stress at P2 is

1 1 : 2  
2 2 : 1  
3 1 : 4  
4 3 : 2  

Ans.

(3)

At P2, Stress=S2=FA

At P1, Stress=S1×Fcos60°Acos60°=F4A

⇒S1S2=14