6. What does the slope of a velocity-time graph indicate?

The slope of a velocity-time graph indicates the acceleration of the object.

Here's the step-by-step explanation:

1. A velocity-time graph shows how the velocity of an object changes over a specific period of time.

2. The slope of a graph is a measure of how steep the line is. In a velocity-time graph, the vertical axis (y-axis) represents velocity and the horizontal axis (x-axis) represents time.

3. When you calculate the slope of a line on a velocity-time graph, you're dividing the change in velocity by the change in time. This is the definition of acceleration.

4. Therefore, the slope of a velocity-time graph represents the acceleration of the object. If the slope is positive, the object is speeding up. If the slope is negative, the object is slowing down. If the slope is zero, the object is moving at a constant velocity.