A body is in motion if it change its position relative to another body or with respect to a frame of reference or coordinate system.
If its position in relation to the origin has change.
i dont know . why?
I don't know, and I guess you won't know either, so no body knows! How about that?!
A net force on a body can stop the motion of a body , can create the motion of a body and can change the direction of motion of a body .
no when the body the body is in motion only
When an object changes its position with respect to time, then the body is said ti be in 'motion'. When the body is at rest, it is state of 'no motion'.
Linear Motion is motion of object/body along a straight line.Random Motion is the motion of an object/body along a disordered or irregular line.
when a body moves along a curved line , the motion described by the body is called curvilinear motion
when position of the body with respect to an observer change with time then the body are said to be in motion.
the tendency of a body at rest to remain at rest and of a body in motion to remain in motion
It is usually damped harmonic motion.
Friction.