Rotary (Gears) question -- angular acc/velocity involved

1. The problem statement, all variables and given/known data







2. Relevant equations



w (angular velocity) = alpha (angular acceleration) t

w1 / w2 = r2 / r1

|a| = sqrt( (a(tangential))^2 + (a(normal))^2 )





3. The attempt at a solution



Since A has a constant angular acceleration, w = alpha t



For gears A, B: wA/wB = r2/r1

For gears B, small B: wB = w(small B)

For gears small B, C: wC = r1/r2 * ((r1*wA) / r2)

Thus wC = ((r1)^2 * wA) / (r2)^2

And thus wC = ((r1)^2 * alpha * t) / (r2)^2

Subbing in values... wC = (150^2 * 14 * 0.8) / 250^2 = 4.032 rad/s



Now



wA = 0

alpha A = 14



and



wC = 4.032

alpha C = (r1 * alpha A) / r2 = 8.4





So



a(tangential) = alpha C * r2 = 2.1

a(normal) = (wC)^2 * r2 = 4.064

|a| = sqrt( 2.1^2 + 4.064^2) = 4.57



However this is not correct...



Could someone point out where I may have gone wrong?



It would be greatly appreciated, thank you

via Physics Forums RSS Feed http://www.physicsforums.com/showthread.php?t=713246&goto=newpost