A mass 3kg at the temperature 850°c is quickly transferred into a lead calorimeter of negligible heat capacity containing water of mass 500g at 20°c. Evaluate the mass of that boils away given the specific heat capacity as 400JKg-1K-1 and specific heat of vaporization steam as 2.26 × 10^5kg.

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.