If the _______ of a body changes with time, it is said to be in motion.
direction
speed
position
distance
If the position of a body changes with time, it is said to be in motion.
A body is said to be in motion if its position changes with respect to time.
A car is standing at a distance of 2 m in the east direction from a tree. If the position of the car does not change with time, the car can be said to be in motion with respect to the tree.
When the position of a body with respect to its surrounding/observer doesn’t change with time, the body is said to be in motion.