Physics

Problem

A boat moving along a straight river has the following velocity–time data: • It decreases uniformly from

12\,\text{m/s}

0

4\,\text{s}

, • then accelerates uniformly to

-8\,\text{m/s}

in the next

3\,\text{s}

(negative sign means opposite direction), • and finally continues at

-8\,\text{m/s}

for

6\,\text{s}

. Determine the total displacement of the boat over the entire

13\,\text{s}

described.