About displacement–time graphs

A displacement–time graph shows how far an object is from its starting point along a chosen axis, and in which direction, as time passes. Here we use the vertical (y) axis: above the origin is positive displacement; below the origin is negative displacement.

The gradient (slope) tells you the velocity along that axis:

• Positive gradient: moving upwards.
• Negative gradient: moving downwards.
• Horizontal line: stationary vertically.
• Steeper gradient: higher vertical speed.
• Curved line: changing vertical velocity (accelerating or decelerating).