A vertical spring supports a block in equilibrium. The spring is designed to break when extension in it crosses a limit. There is a light thread attached to the block as shown. The thread is pulled down with a force F which gradually increases from zero. The spring breaks when the force becomes `F_0`. Instead of gradually increasing the force, if the thread were pulled by applying a constant force, for what minimum value of the constant force the spring will break?

Answer

`(F_(0))/2`