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XwyhyX
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Homework Statement
An aluminum wire is 0.850 m long and has a circular cross section of diameter 0.780 mm. Fixed at the top end, the wire supports a 1.20-kg object that swings in a horizontal circle. Determine the angular velocity required to produce a strain of 1.00 10–3.
Homework Equations
Y of Aluminum = 7.0x1010
Y = [itex]\frac{Stress}{strain}[/itex]
Stress = [itex]\frac{F}{A}[/itex]
Fc = ω2R
The Attempt at a Solution
I use Young's Modulus with the definition of stress and I get the equation
Y = [itex]\frac{F/A}{Strain}[/itex]
Then I can solve for F
A = [itex]\frac{∏(0.780)2}{4}[/itex] = 4.77x10-7
F = Y x Strain x Area
Okay, now I have the force which will give me the strain that is needed. I'll apply it in an object rotating in a horizontal circle, The force that I used will be the one on the X axis. So
Fc = Fsinθ
and also
R = Lsinθ
Using the equation of Centripetal Force I get the equation for angular Velocity
ω = [itex]\sqrt{\frac{Tsinθ}{Lsinθ}}[/itex]
Finally I get the value of 6.27 rad/s
I just want to know if I did it right. Because I don't have the correct answer for this. Thanks :D