 #1
 18
 0
Homework Statement
See image.
Homework Equations
ωx (ωx r) = anormal
αx r =atangent
x=rcos*theta
y=rsin*theta
The Attempt at a Solution
I solved for w=2 k rad/s and α= 1.5 k rad/s
I also got the correct answer using the cross products. My problem is I am trying to do this problem in rectangular coordinates (I really like rectangular), but I am doing something wrong and I cannot see it.
So, I assume r is constant:
x''=r*cos(45)[ω^2α] = Correct answer= 15.566
BUT, y'' is giving me a headache:
I keep getting rsin(45)[ω^2α] and I get = 15.66 and NOT the right answer of 7.07 in/s. There is a lurking negative sign and I cannot find it. That  should be a + and then I get a correct answer. Am I just deriving incorrectly?
Thanks!!
And apologizes if this is pretty novice: its from my Juniorlevel engineering class...or a freshman Physics class. ;p
Attachments

41.5 KB Views: 317
Last edited: