What does it mean when the mark on the ramrod disappears into the barrel of the muzzleloader?

The firearm is unloaded.

The ramrod establishes whether the firearm is loaded or unloaded. It thrusts the bullet down the barrel. It is marked by wrapping some tape around it ( at the muzzle end ). This is to effectively signal if the muzzleloader is empty or loaded.

the electric field is a “force field” around a charged object that illustrates the direction the electric force would push an imaginary 

a displacement distance is size of displ