$A$ girl running a race accelerates at $2.5 \, m s^{-2}$ for the first $4 \, s$ of the race. How far does she travel in this time (in $, m$)?

State whether the following statement is true or false:
$A$ quantity which can be completely specified by magnitude as well as direction is called a scalar quantity.

What does the odometer of an automobile measure? Which of the following is moving faster? Justify your answer.
$(i)$ $A$ scooter moving with a speed of $300 \, m$ per minute.
$(ii)$ $A$ car moving with a speed of $36 \, km$ per hour.

$A$ particle is moving in a circular path of radius $r$. The displacement after half a circle would be:

$A$ body moves with a velocity of $2\, m s^{-1}$ for $5\, s$,then its velocity increases uniformly to $10\, m s^{-1}$ in the next $5\, s$. Thereafter,its velocity begins to decrease at a uniform rate until it comes to rest after $5\, s$.
$(i)$ Plot a velocity-time graph for the motion of the body.
$(ii)$ From the graph,find the total distance covered by the body after $2\, s$ and $12\, s$.

The distance-time graph of two trains is given below. The trains start simultaneously in the same direction.
$(i)$ How much ahead of $A$ is $B$ when the motion starts?
$(ii)$ What is the speed of $B$?
$(iii)$ When and where will $A$ catch $B$?
$(iv)$ What is the difference between the speeds of $A$ and $B$?
$(v)$ Is the speed of either train uniform or non-uniform? Justify your answer.