Skip to content
dronacharya.ai
← JEE Main 2014 · 12 Apr · Shift 1
PhysicsSingle correct+4 / -1Question 8 of 90

JEE Main 2014 · 12 Apr · Shift 1, Physics question 8

Steel ruptures when a shear of 3.5×1083.5\times10^8 N m−2^{-2} is applied. The force needed to punch a 1 cm diameter hole in a steel sheet 0.3 cm thick is nearly :

Choose one option
Answer and worked solution

Official answer: C

The sheared area is the side of the punched cylinder: πdt=π(0.01)(0.003)=9.42×10−5\pi dt=\pi(0.01)(0.003)=9.42\times10^{-5} m².
F=3.5×108×9.42×10−5≈3.3×104 N.F=3.5\times10^8\times9.42\times10^{-5}\approx3.3\times10^4\text{ N}.