Recent content by joe465

Thankyou for the link, finally came across http://www.ehow.com/info_10062949_effects-altitude-aircraft-wiring.html with some basics on it, should be enough to tie me over combined with your link. Thanks very much guys.

Thanks, it is for an aircraft, it is generator cables for a 747. No environment stated so i could possibly just go with the 2 degree decrease every 1000 feet?. What would you recommend?

Hi Guys, Struggling to find any information on the changes to a cable at altitude compared to at sea level. The initial task was to calculate the resistance of generator wires and then change them from copper to aluminium cables to save weight. I have done this leading me onto describing the...

Yeah i went for steel because the stress strain shows two yield points which is a common steel reflection. Now just material Z. My tutor said it should be between 500-600 Pascals but i can't get this value at all no matter which units i use? Stress Strain 70 0.06 100 0.11 150 0.22 200 0.35 220...

Still having problems finding which materials they are. Material Y young's modulus is 270 GPa and looking at the stress strain graph it has a UTS of 700 MPa. I can't find a material which matches this, please help. Chromium has a Young's Modulus of 279 GPa but i can't find the UTS anywhere.

Any ideas how i could prove which material they are from the Young's Modulus? Calculate anything else to back up the argument?

I've used the gradiant that was already drawn and i got Material X = 185.185 GPa Material Y = 270.270 GPa Material Z = 3.63636 × 10-7 GPa Material X = Possibly Tantalum at 186 Material Y = Maybe Chromium at 279 Material Z = ? Not sure about Material Z, doesn't seem like anything is even...

Thanks, Does this mean that the gradient i.e Difference in Y / Difference in X would give me the correct answer and the second formula is not required? Gradient = Difference in Y axis / Difference in X axis Gradient = 150000000 – 100000000 / 0.00187 – 0.0016 Gradient = 185185185185.185 (3 dp)...

Which formula is right? Or are both used? There seems to be a few online suggesting different things. Joe

Thanks, so to find the Young's Modulus i need to find the gradient of the slope being: Gradient = Change in Y axis / Change in X or is it Young's Modulus = Original length/(gradient * CSA) Would you recommend me re-drawing the graph with using only a few pieces of data allowing for more...

I've double checked them and i can't see where its wrong. The extension was pre-given in mm and the Original length of sample was also pre-given in mm. Strain = Change of Length / Original Length For Material X Original Sample Length = 375mm Ext (mm) / Original Sample Length (mm) 0.48...

Thankyou, all the Load and extension data was provided. The area i believe to be correct and I'm confident my calculations are correct so any idea what to do now?

So your suggesting the graph starts in mid air? I'm not sure what you mean but I'm confident i have to use arithmetic graphs and not log. Do i just use the gradient to determine Young's Modulus? So Change in Y axis / Change in X axis? I have very little time left to get this done, i need to get...

Thankyou, my initial task was to calculate the CSA which i did at 0.00002m2. I was pre-given Load and Extension data for 2 materials and given Stress-Strain data for the third. I was tasked to calculate the stress-strain data for all three and then plot the relevant graphs. Material X TEST...

http://imageshack.us/f/194/materialx.jpg/ http://imageshack.us/f/38/materialy.jpg/ http://imageshack.us/f/209/materialz.jpg/ http://imageshack.us/f/194/materialx.jpg/ http://imageshack.us/f/38/materialy.jpg http://imageshack.us/f/209/materialz.jpg There are the three stress-strain graphs