Describe in words the motion plotted in Fig. 2-32 in terms of velocity, acceleration, etc. [Hint. First try to duplicate the motion plotted by walking or moving your hand ]

Solution 21Q

We will describe the plotted graph of a motion above.

But we need to know what how to read the speed from the graph

Slope

The slope of x-t graph of a motion gives velocity

The x-t graph of car A is given aside. The slope of the graph gives its velocity.

The x-t graph of car B is given aside.

The slope of car A is bigger than slope of carB. So velocity of car A is bigger than car B. In both two motions above, the velocity of the objects are constant , the slopes of the graphs are constant

The x-t graph of car C is given aside. It is a curve, so its slope is changing. If slopes changes velocity changes.

The slope of the line tangent to graph at point gives velocity of object at that point.

Step 1 of 2</p>

We will draw the tangent lines to the graph at different points to see the velocity change.