Consider this line graph that represents speed in meters/second. The X-axis is labelled in seconds; the Y-axis is labelled in me
ters. Imagine that the moving object stops after 2.5 seconds and stays stopped for 0.5 seconds. What would the line for that time interval look like on this graph?
If the x-axis represent time and the y-axis represents distance, then the SPEED in meters/second is the SLOPE of the line on the graph.
The object is moving, so the line is either rising or falling, but it's definitely not staying horizontal, because the distance is changing.
The object stops moving at 2.5 seconds, and stays stopped for 0.5 second. So right at the 2.5 sec point, the line stops sloping, and becomes horizontal until 3.0 sec.
We don't know what happens then. If the object stays still for longer, then the line stays horizontal until the object starts moving again. Then the line starts sloping again.
To represent no movement of distance/time graph, the line would have no slope. In this case, the line would be straight and horizontal at Y equals 14, to {3, 14}.
When the temperature increases the volume will increase, and when it cools it will decrease. This is because the molecules spread further apart as the temp gets higher, which creates a bigger volume.
