what is psudo force? where does it originate from?

Answer 1

If you were talking physics forces that would be a force vector that is not physically there but is the vector sum of several existing physical forces.

An example would be a pseudo force that pulls to the North East but is actually the result of a force pulling to the North combined with another force pulling to the East.

Answer 2

Pseudo force is a fictitious force which is physically apparent but non-existent. For example, you notice that when the washing machine drum accelerates to high speed during the dry cycle, the drum is hollow in the center with the laundry moving and clinging to the sides of the drum even when there is no real mechanism that pushes the laundry to the sides of the drum. This is because when the drum accelerates, so does the laundry and since the laundry has a mass it experiences a force(F=ma). This force is the centrifugal force which is a pseudo force. So a pseudo force originates when a mass is in an accelerating frame of reference (drum in this example). Such a frame of reference is also called a non-inertial frame of reference and a mass in such a frame violates Newton's laws of motion.