State how the velocity-time graph can be used to find the acceleration of the body.

Two athletes are moving along a straight track. A figure shown below represents a displacement-time graph to display the movement of these two athletes. Find out who is moving faster. Give reason.

A particle moves $12 \mathrm{m}$ to east and then through $5 \mathrm{m}$ to north. Now, the net displacement is $K \mathrm{m}$. Find the value of $K$.

A body starts from rest and acquires a velocity $10 \mathrm{m} {\mathrm{s}}^{-1}$ in $2 \mathrm{s}$. Find acceleration of the body in $\mathrm{m} {\mathrm{s}}^{-2}$

In the given figure, the displacement of an object is shown at different times. Calculate the velocity of the object as it moves from $0$ to $5 \mathrm{s}$, $5 \mathrm{s}$ to $7 \mathrm{s}$, $7 \mathrm{s}$ and $9 \mathrm{s}$.

A car travels with a uniform velocity of $30 \mathrm{m}/\mathrm{s}$ for $5 \mathrm{s}$. The brakes are then applied and the car comes to rest with a uniform retardation in a further $10 \mathrm{s}$. Draw a velocity-time graph and use it to find the distance with which the car travels after the brakes are applied.