Statics Problem involving blocks, rope, pulleys and springs....

[jbakes]

Homework Statement

The angle at the bottom is 25 degrees

Homework Equations

Springs Parallel;
keq = k1 +k2
Sum Forces = f1 + f2
x = f1/k1 = f2/k2

Springs Series;
1/keq = 1/k1 + 1/k2
Sum x = x1 +x2
F = k1x1 =k2x2

The Attempt at a Solution

Basically I'm having trouble finding the spring constant (Keq)23
I've worked out all the diagrams and if I could just find the spring constant I could then plug it into my FBD@E and find the tension. Then from there I can plug the tension into my Moment equation and find the force in spring one and solve for x.

 

[CWatters]

I think you should show your working.

I haven't attempted to solve the problem (and not sure I can) but I note that they ask you to calculate the spring constant in Q3. That's possibly a clue that the spring constant isn't needed to work out the answer to Q1 and Q2.

 

[scottdave]

Look at point A. That rope pulls up with a certain tension. This is tied to a spring, which must pull up with the same tension as the rope at A, since nothing is accelerating. So this brings us to point G: The spring must be pulling down at G with the same force as it is pulling up. You should be able to find the vertical forces at G, in terms of the main Tension and the angles. Take this upward force with the upward Tension at C, then the block B weight, and sum the moments about D, to solve for the Tension.