A 50 kg chandelier is hung from the ceiling by an alumnum wire (initially 2m long).
A)know the ultimate tensile stress of aluminum is 200 MN/m^2,find the minimum diameter of the wire needed to supposrt the chandelier

B)When the ful weight of the chandelier puls the wire, by how much does it stretch. Use 70GN/m^2 for alminium Y ? is this stretch reasonable

Question

A 50 kg chandelier is hung from the ceiling by an alumnum wire (initially 2m long).
A)know the ultimate tensile stress of aluminum is 200 MN/m^2,find the minimum diameter of the wire needed to supposrt the chandelier

B)When the ful weight of the chandelier puls the wire, by how much does it stretch. Use 70GN/m^2 for alminium Y ? is this stretch reasonable

anonymous · Answer

$$Stress=\frac{F}{A}$$
weight is the force acting upon the wire perpendicularly 

$$Stress=\frac{mg}{A}$$
A is circluar so using circle area

$$Stress=\frac{mg}{2\pi r^2} $$
$$r=\sqrt{\frac{mg}{2\pi*stress}}$$

anonymous · Answer

hmm thats weird the answer in the answer key is different

anonymous · Answer

@Spectrum

anonymous · Answer

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