Positive charge Q=5 nC is placed on a conducting spherical shell with inner radius R1=20 cm and outer radius R2=30 cm . A particle with charge q=4 nC is placed at the center of the cavity. What is the magnitude of the electric field at a point in the cavity, a distance r=12 cm from the center? (Take Coulomb's constant k=9x10 9 N m2 /C2)

Kiloleter, mega leterhope 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.