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1. Homework Statement
A figure is attached.
The symmetric system consists of 4 massless rodes with length 'L',the purple thing is a spring(the spring constant is k),when the system is at rest theta=45 deg.
the system starts to rotate with angular speed 'w',the rodes are pushing on the spring and theta is getting smaller.
I need to express theta using:L,m,k,w.
3. The Attempt at a Solution
the length of the spring when the system is at rest is: sqrt(2)*L
so the force is: k(2*sin(theta)*L  sqrt(2)*L) = 'F'
I tried to apply newton's second law:
F = ma = m*w^2*R = 2m*w^2*Lcos(theta)
where Lcos(theta) is the radius.
but the answer is wrong..
A figure is attached.
The symmetric system consists of 4 massless rodes with length 'L',the purple thing is a spring(the spring constant is k),when the system is at rest theta=45 deg.
the system starts to rotate with angular speed 'w',the rodes are pushing on the spring and theta is getting smaller.
I need to express theta using:L,m,k,w.
3. The Attempt at a Solution
the length of the spring when the system is at rest is: sqrt(2)*L
so the force is: k(2*sin(theta)*L  sqrt(2)*L) = 'F'
I tried to apply newton's second law:
F = ma = m*w^2*R = 2m*w^2*Lcos(theta)
where Lcos(theta) is the radius.
but the answer is wrong..
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