The numerical ratio of displacement to distance for a moving object is

When is the acceleration $(i)$ positive and $(ii)$ negative?

If the displacement-time graph for a particle is parallel to the displacement axis,what is the velocity of the particle?

Suppose a boy is enjoying a ride on a merry-go-round which is moving with a constant speed of $10 \, ms^{-1}$. It implies that the boy is

$(a)$ Differentiate between distance and displacement.
$(b)$ Under what conditions is the magnitude of average velocity of an object equal to its average speed?

$A$ person standing at $A$ goes to $B$ by following any of the paths $1, 2$ or $3$. Which path can we measure to find the average velocity?