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ajprincess
Please help:). the maximum amplitude and the maximum acceleration of the foundation of an industrial fan were found to be x_max=0.2mm and a_max=0.3
Here |dw:1352046269529:dw|
so whats the question, that is correct \(a=\ddot x\) where differentiation is w.r.t time.
oops sorry forgot to post the question
Determine the operating speed of the fan.
|dw:1352046585292:dw| Am I right?
if u take x as sinusoidal, then x_max = A=0.2mm are you suppose to take it as sinusoidal ?
i am nt sure. Bt in the answr given they use \(x=Acos(\omega t)\) i dnt get why they use it.
i would write that in this manner , you are correct numerically. |x|=A , \(|\ddot x |=Aw^2\) so w^2= 0.3/0.2 as A=0.2 and \(|\ddot x |=0.3\)
and this speed you will get it in rad/sec ofcourse by taking sqrt of w^2
where do we use \(x=Asin\omega t\) and \(x=Acos\omega t\)? Are they equal? I am nt getting this.
they aren't equal. just phase shift of pi/2 so either of them can be used. but in this question even it doesn't make sense to me using sinusoidal wave for fan equation, if it is given, then its ok.
so what equation should be used here @hartnn?
not sure, need to google it ..but since in your given answer sine waves are used, your teacher/course must expect u to take it as sinusoidal everytime....
Ha k. Thanxxxxx a lot for helping me:)