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dimpledur
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Homework Statement
Spider Silk has a Young Modulus of 4.0x10^9 N/m^2 and can withstand stresses of up to 1.4x10^9 N/m^2. A single webstrand has a cross sectional area of 1.0x10^-11 m^2, and a web is made up of 50 radial strands. A bug lands in the centre of a horizontal web. With what mass should the bug be to exert this maximum stress?
Homework Equations
F/A = 1.4x10^9 N/m^2
The Attempt at a Solution
F/A = 1.4x10^9 N/m^2
mg / A = 1.4x10^9 N/m^2
A = 50 strands * 1.0x10^-10 N/m^2 = 5.0x10^-10
so m = (1.4x10^9 N/m^2)(5.0x10^-10) / 9.8
m = 71.4g
HOWEVER, the answer is 48 grams. I am unsure of what to do with the area. Like, I'm pretty sure that I am messing that portion up.