When a hole of diameter d is punched in a metal of thickness 't', then the force required to punch a hole is equal to (where τu = Ultimate shear strength of the material of the plate)
d.t.τu
πd.t.τu
π/4 × d².τu
π/4 × d² × t.τu
Correct Answer :
B. πd.t.τu
Related Questions
In a hydrodynamic lubricated bearing
There is a thick film of lubricant between the journal and the bearing
There is a thin film of lubricant between the journal and the bearing
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Resistance to fatigue of a material is measured by
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Endurance limit
According to Indian standards, total numbers of tolerance grades are
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Which of the following statement is wrong?
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Comformability
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Both A and B
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Yield strength
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Mechanical advantage to the velocity ratio
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In increasing the slip of the belt
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Keeping the core diameter of threads equal to the diameter of unthreaded portion of the bolt
Keeping the core diameter smaller than the diameter of the unthreaded portion
Keeping the nominal diameter of threads equal to the diameter of unthreaded portion of the bolt
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Shear stress
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Fatigue stress
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Butt joint with double cover plate
Lap joint with one ring overlapping the other
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Pitting at points or areas at which loads on a member are applied
Abrupt change of section
All of the above