resistance





source document :  source : SNAME vol ii






components:

1. Frictional resistance: due to motion of hull through a fluid that is its character is viscous
2. wave-making resistance: due to the energy that additionally must be supplied continuously by the ship to the wave system. The so called "wave system" was created on the water surface.
3. eddy resistance: energy that carried away. That energy due to eddies shed from the hull + appendages.
4.  Air resistance.
Note :  normally there is another name, which is called as "residuary resistance". It is the combination of wave-making and eddy resistance. 


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