91影视

The displacement of an object is the shortest distance between its initial and final positions.

The motion of the truck can be represented on a graph (taking upward direction as north), as shown below.

Here, the initial and final positions are represented by A and B, respectively.

Let the displacement vector in the east direction be $\stackrel{鈫�}{x}$, the magnitude of which can be represented as $\left|\stackrel{鈫�}{x}\right|=16$.

Similarly, let the displacement in the south direction be $\stackrel{鈫�}{y}$, the magnitude of which can be represented as $\left|\stackrel{鈫�}{y}\right|=5$.

Let the net displacement vector be role="math" localid="1644220421181" $\stackrel{鈫�}{\mathrm{AB}}$, with magnitude AB.

All these vectors can be represented on a vector diagram, as shown below.

The magnitude of the net displacement vector $\stackrel{鈫�}{\mathrm{AB}}$, in terms of $\left|\stackrel{鈫�}{x}\right|$and $\left|\stackrel{鈫�}{y}\right|$, can be obtained using the Pythagoras theorem.

$\begin{array}{c}{\left(\mathrm{AB}\right)}^2={\left|\stackrel{鈫�}{x}\right|}^2+{\left|\stackrel{鈫�}{y}\right|}^2\\ ={16}^2+5^2\end{array}$

From the above equation, $\mathrm{AB}=16.76\mathrm{blocks}$.

Thus, the displacement of the truck is 16.76 blocks.

Let the net displacement vector $\stackrel{鈫�}{\mathrm{AB}}$make an angle $胃$in the clockwise direction from the direction representing east. From the definition of the tangent function, the value of $胃$is${\tan }^{-1}\left(\frac{5}{16}\right)=17.35掳.$

Thus, the direction of net displacement is $17.35掳$below the east direction.