Question

a. Distinguish between acceleration and retardation.
b. Draw speed-time graph for freely falling body.
c. Draw a diagram showing the motion of a lift starting from the ground floor , slooping at the third floor and finally reaching the fifth floor.

Answer 1

a) Acceleration is always positive and retardation means negative Acceleration

Answer 2

Rate of change of velocity is called as acceleration. If the particle is slowing down, reducing its velocity, its acceleration is negative. ... Mos simple way to describe deceleration is when the speed of a body decreases.
Retardation is used in general context, it also means same as deceleration