A body moves along a straight line with uniform acceleration.
a. (i) Define average velocity for any time interval.
b. (ii) Using the ideas of displacement and uniform acceleration, explain logically why the numerical value of average velocity for the complete interval equals 2u+v, where u is the velocity at the beginning and v is the velocity at the end of the interval.
c. (iii) Would the relation given in part (ii) remain valid if the acceleration were not uniform? Give a reasoned argument.