The displacement $(x)$ and time $(t)$ graph of a particle moving along a straight line is shown in the figure. The average velocity of the particle in the time of $10 \ s$ is (in $m \ s^{-1}$)

Distinguish between uniform velocity and non-uniform (variable) velocity.

$A$ person travelling on a straight line moves with a uniform velocity $v_1$ for a distance $x$ and with a uniform velocity $v_2$ for the next $\frac{3}{2} x$ distance. The average velocity in this motion is $\frac{50}{7} \ m/s$. If $v_1$ is $5 \ m/s$,then $v_2 = $ . . . . . . $m/s$.

$A$ person travels $x$ distance with velocity $v_1$ and then $x$ distance with velocity $v_2$ in the same direction. The average velocity of the person is $v$. Then the relation between $v, v_1$ and $v_2$ will be:

$A$ car moves from $A$ to $B$ with a speed of $30 \ km/h$ and from $B$ to $A$ with a speed of $20 \ km/h$. What is the average speed of the car (in $km/h$)?

Is the statement "$A$ particle can have zero speed but non-zero velocity" true or false? Explain.