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Discussion => Off topic => Topic started by: DSiddious on May 22, 2012, 12:26 am

Title: A ? for any Engineers out there.
Post by: DSiddious on May 22, 2012, 12:26 am
I was hit by a problem at work today and i am ashamed to admit it is not my area of expertise. I try to spell it out simply, > means to the power . A pulley is accelerated uniformly from rest at a rate of 8rad/s>2. After 20s the acceleration stops and the pulley runs at constant speed for 2 min, and then the pulley comes uniformly to rest after a further 40s. What we need out of this is A/ the angular velocity after the period acceleration B/ the total number of revs made by the pulley. Any help would be very much appreciated and would help me with a job I've been working on for weeks now.     
Title: Re: A ? for any Engineers out there.
Post by: opi on May 22, 2012, 01:03 am
I can help you out, once I go home and check some formula's. I did this shit in my dynamics course years ago....

I don't remember the angular ones but I remember the linear ones..

v^2 = Vi^2 + 1/2at that will give you the final Vel. as V = W(angular vel) and A is equal to angular accell.

I am not 100% sure on the formula like I said I will check once I go home and find my notes.
Title: Re: A ? for any Engineers out there.
Post by: DSiddious on May 22, 2012, 07:46 am
Cheers man you'll be doing me a massive favor. Angular motion is rather hard to say the least (well to me anyways.)
Title: Re: A ? for any Engineers out there.
Post by: opi on May 22, 2012, 08:41 am
ugh, I totally forgot to look for my notes... and now I gotta study for my finals (got two today..)
Title: Re: A ? for any Engineers out there.
Post by: killerbunnies on May 22, 2012, 08:46 am
Need to know the radius of the pulley. There seems to be other things missing from the problem as well, such as the description of the pulley system (i.e. are there weights attached?) If you can post the problem on here word for word I can reply with a step by step how to solve it.