An object may be regarded to be rest or in motion depending on the frame of reference chosen to view the object. Because of length contraction it would mean that the same rod may have two dfferent lenghts depending on the state of the observe. Is this true ?

Answer the following as true or false. (i) A zero vector cannot be assigned a definite direction. (ii) A zero vector may be regarded as having any direction. (iii) Two vectors are equal if they have same magnitude and direction regardless of the position of their initial points. (iv) The length of a unit vector is 2.