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Homework Statement
Collars A and B slide along the fixed rightangle rods and are connected by a cord of length L = 7 m. Determine the acceleration of collar B when y = 2.2 m if collar A is given a constant upward velocity v_{A} = 2.66 m/s. The acceleration of B is positive if to the right, negative if to the left.
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Homework Equations
x^{2}+y^{2} = l^{2}
3. The Attempt at a Solution [/b
I found the distance x, from the base of the support to B to be 6.64529 m
I took the derivative of the Pythagorean to get:
2xx' + 2yy' = 0
Then I took the derivative again:
2x'x' + 2xx" + 2y'^{2} + 2yy"
Solving for x" = x'^{2}  y'^{2} yy"/x
x" = (yy'/x)^{2}  y'^{2}/x
x" = 0.9057
But it says it's wrong. Where is my mistake?
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