A force of 50 newtons is a measure of force, and its value can depend on the context:
On Earth, it is roughly the amount of force needed to lift about 5 kg (since 1 kilogram weighs about 9.8 newtons due to gravity).
In pounds-force, 50 newtons is about 11.24 pounds-force (lbf).
It’s essentially the strength or push needed for a given task but doesn’t have a direct cost unless it’s related to specific equipment or machinery.