Solving Preloaded Springs w/ Mass: Can Force Overcome Preload?

[Buns_of_Steel]

Quick question that's causing a lot of headaches at the moment.

Ive got two horizontal springs with a mass in the middle.
The springs are preloaded.
I get that the springs are in parallel and the effective stiffness is the sum of the stiffnessess.

If the springs are preloaded, is the preload effectively canceled because the springs are opposing each other? I.e. if i apply a force to the mass, does it move or does the force need to overcome the spring preload?

Cheers

 

[Baluncore]

If the springs are preloaded, is the preload effectively canceled because the springs are opposing each other? I.e. if i apply a force to the mass, does it move or does the force need to overcome the spring preload?

Yes, the preloads cancel. The mass will move immediately you apply a force.

 

[BvU]

Make a drawing, indicate all the forces. Is the initial state at equilibrium ?