How Much Force to Punch a Hole in Steel?

[Myung]

Homework Statement

How much force is required to punch a hole 1/2 inch in diameter from a 1/8 inch thick sheet of steel with a shearing strength of 4x10^4 PSI?

Homework Equations

Formula goes like this

Shearing Modulus = (Force/Area) / (Shearing Length/Length to be sheared)

The Attempt at a Solution

Force = ?
Area = ∏(d^2/4)
Shearing Length = ?
Length to be sheared = 1/8 inch

My problem now is i cannot find out how to get the shearing length that is needed to solve the equation.

Solving the equation regardless of the shearing length value will yield:

= 63 kPSI * Shearing Length

 

[Myung]

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