Question

how is constant velocity indicated on a motion map?
by vectors that slowly increase in length
by vectors that are all the same length
by dots that slowly increase in size
by dots that are all the same length

Explanation:

In a motion - map, velocity is represented by vectors. Constant velocity means the speed and direction do not change. So, the vectors representing the velocity will have the same length (indicating constant speed) and the same direction. Dots are used to represent the position of an object at different times and their size is not related to velocity. Also, dots don't have a "length" in the context of representing velocity. Vectors that increase in length indicate increasing speed, not constant velocity.

Answer:

B. by vectors that are all the same length