Write any two equations of motion for a body having uniform acceleration.

$A$ body is moving along a circular path of radius $R$. Find the displacement of the body when it completes half a revolution.

$A$ bus decreases its speed from $80 \, km \, h^{-1}$ to $50 \, km \, h^{-1}$ in $4 \, s$. Find the acceleration of the bus.

The velocity-time graph of cars $A$ and $B$ which start from the same place and move along a straight road in the same direction is shown below.
Calculate:
$(a)$ The acceleration of car $B$ between $2 \, s$ and $4 \, s$.
$(b)$ The time at which both the cars have the same velocity.
$(c)$ The distance travelled by the two cars $A$ and $B$ in $8 \, s$.
$(d)$ Which of the two cars is ahead after $8 \, s$ and by how much?

$A$ hiker rides $700\, m$ north,$300\, m$ east,$400\, m$ north,$600\, m$ west,$1200\, m$ south,$300\, m$ east,and finally $100\, m$ north. Draw the path of motion of the hiker. What distance did he cover? What was his displacement?

State whether the following statement is true or false:
$A$ motion is said to be uniform if $x \propto t^{2}$.