Hai quả cầu kim loại nhỏ giống nhau mang điện tích q1 = 3 μC và q2 = -12 μC. Cho hai quả cầu tiếp xúc nhau rồi đặt hai quả cầu cách nhau 3 m. Lực tương tác tĩnh điện giữa chúng khi
đặt trong không khí là:
A. 20,25.10-3N.
B. 36.10-3N.
C. 2,025 N.
D. 0,36 N.

Ibelieve your answer is b.hope this : )

You need to be more specific.  i really don't know what a "motion map" is.you can draw a graph of an object's position, distance, displacement, speed,velocity, or acceleration versus time, or you can draw a graph of the object's x-position versus its y-position and not give any information about time at all.if the graph presents position or displacement against time,  then constant velocity is a straight line . . i.e. a line that has  constant slope.if the graph shows speed against time, then constant velocityis a horizontal piece of line.if the graph shows acceleration against time, then constant  velocity is a piece of line that lies on the x-axis . . it's value is zero.