Recent content by RichMortimer

Haaaaaaaaaaaaa haaa! Just got it! I must be a singular. Therefore there is a 1 in front. 1/0.565 = 1.77 :-D Therefore: h=(v^2(m*r^2+I)) / (2*g*m*r^2) is equal to h=v^2(0.051+1.77*I) Wow. Thanks again cepheid... :)

Ok, sorry about quality, just easier than trying to type it all out! See attached... I feel like I'm nearly there but I'm not sure how to bring the 2*g*m*r^2 out from below. I know I'm on the right lines as I can equate the 0.051 required but as yet figured where the 1.77 has come from...

A clear rested mind is a wonderful thing! I've just read your last post... I realize that I had indeed been asking the wrong question! I don't need a value for h or v as they are unknown in the given equation! I'll have a go at the question again and feed back. Once again, thank you!

So would you just pick a random height? Or try working backwards from the given equation? I'll try again in the morning and re-post. See where we get to! Thanks, Night.

Hello cepheid, Thanks for the reply. I initially thought something similar, using the radius. However, unless I "create" a height and time value I can't see how I relate to the function h = v^2(0.051+1.77xI) I'm assuming I can somehow find a connection between the above values and a PE...

A solid circular flywheel around which a string is wrapped. At the end of the string is a 2 kg mass. If the mass is dropped, the drum will rotate. After the mass has fallen h metres, it has a velocity of v m/s and the wheel has a rotational velocity of ω rad/s The flywheel radius is 120...

Ha... That now makes sense! Thanks again.

Ah I see, Sorry, I figured I couldn't see any more as it was locked! Guess I'll have to start again at the beginning then. Thank you both for the quick response and help. :)

Evo, the locked thread is: https://www.physicsforums.com/showthread.php?t=175160 But I can only see first two posts. Zz, Thank you!

Hi Evo, That will be why then! Thanks. Is it possible to re-open this or is it lost forever? Thank you!

Hi, I looked for a FAQs area but couldn't find one? I've come across a thread which may help with a problem I have but it is locked? Can anyone help with viewing this? Is there a reason it should be locked? Thank you.

Woooooooooooooooooooooooo Hoooooooooooooooooooooooo! Mr PhantomJay, you have been great! That felt like a long trip, however I feel like I might have actually enjoyed it! Thank you again for the help, have a great day, Rich. P.s. sorry about the ears! :biggrin:

Is the end in site... Ok Phantom Jay, what do you think? "Better do the math(s) again...and please watch units... I get M = 20 000 000 N-mm, roughly" I can get 19 992 000 N/mm if I transpose as M = Stress x I / y but that seems to be wrong as the original formula was stress = M(I/y)...

PhantomJay... Just read your reply. I'm getting straight on it! Thank you!

So I'm typing out loud here! What am I doing wrong?... Is the allowable stress of mild steel an available number? Based on online searches, "Mild steel" is very general! What have I missed in my textbook? Appendix Tables... 1) Tensile strength. Gives range. Tensile not useful now...