- #1

madafo3435

- 55

- 15

[Moved from technical forums, so no template]

(I attach my drawing below)

first calculated the torque:

then i use:

I have problems here, I cannot continue, I appreciate any help.

**Summary::**A rod of length l and mass m, pivoted at one end, is held by a spring at its midpoint and a spring at its far end, both pulling in opposite directions. The springs have spring constant k, and at equilibrium their pull is perpendicular to the rod. Find the frequency of small oscillations around the equilibrium position.(I attach my drawing below)

**The Attempt at a Solution**first calculated the torque:

τ=-F(L/2)sen(θ+90°)-F'Lsen(θ+90°)+mg(L/2)sen(θ)

τ=-F(L/2)cos(θ)-F'Lcos(θ)+mg(L/2)sen(θ)

approaching for small θ:τ=-F(L/2)cos(θ)-F'Lcos(θ)+mg(L/2)sen(θ)

τ=-F(L/2)(1-θ^2/2)-F'L(1-θ^2/2)+mg(L/2)θ

replacement:

F=K(L/2)θ

F'=KLθ

F'=KLθ

then i use:

τ=Iθ''

I have problems here, I cannot continue, I appreciate any help.

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