Distinguish between the terms distance and displacement.

Under what conditions of motion,the distance covered by a body is equal to the magnitude of its displacement?

Mention some uses of velocity-time graphs.

An object starts a linear motion with velocity $u$ and with uniform acceleration $a$,it acquires a velocity $v$ in time $t$.
$(a)$ Draw its velocity-time graph.
$(b)$ Obtain the first equation of motion,$v = u + at$,for the velocity-time relation by using the velocity-time graph.
$(c)$ $A$ body moving with a velocity of $2 \, m s^{-1}$ acquires a velocity of $10 \, m s^{-1}$ in $5 \, s$. Find its acceleration.

$A$ body can have zero average velocity but not zero average speed. Justify this statement by giving an example.

$A$ circular cycle track has a circumference of $314 \ m$ with $AB$ as one of its diameters. $A$ cyclist travels from $A$ to $B$ along the circular path with a velocity of constant magnitude $15.7 \ m s^{-1}$. Find the:
$(a)$ distance moved by the cyclist.
$(b)$ displacement of the cyclist,if $AB$ represents the north-south direction.
$(c)$ the average velocity of the cyclist.