Distance-Time Graphs

Understanding Distance-Time Graphs

  • A distance-time graph represents how an object’s distance from a certain point changes over time.
  • On a distance-time graph, time (t) is usually represented on the x-axis (horizontal), while distance (d) is represented on the y-axis (vertical).

Characteristics of Distance-Time Graphs

  • If the graph is a straight line going up, this indicates constant speed. The steeper the graph, the greater the speed.
  • If the graph is horizontal (flat), this shows that the object is not moving. It’s at a standstill.
  • If the graph is a line that goes downwards, it suggests the object is returning to its starting point.

Speed in Distance-Time Graphs

  • The speed of an object is given by the slope (gradient) of the distance-time graph.
  • When the graph is a straight line, the speed can be calculated as follows: speed = distance/time.
  • This means if the line is steeper (the line is going more upwards), then the speed is greater.

Different Types of Motion

  • Uniform motion is when an object is moving at a constant speed. This is shown by a straight line on a distance-time graph.
  • Non-uniform motion is when an object’s speed is changing. This is represented by a curved line. The steepness of the curve indicates the rate of acceleration or deceleration.

Reading Distance-Time Graphs

  • The start of a journey is represented by the point (0,0) on the graph.
  • The total time of a journey is represented by the furthest point on the x-axis the graph reaches.
  • The total distance travelled during the journey is represented by the furthest point on the y-axis the graph reaches.
  • Stops during the journey are represented by horizontal lines on the distance-time graph.

Plotting Distance-Time Graphs

  • Ensure you label your axes correctly: time on the x-axis and distance on the y-axis.
  • Use the data given to plot points on the graph.
  • Join the points with straight lines or curves, as needed.
  • Check the graph to ensure it things makes sense, such as a stops being represented by horizontal lines and constant speed by straight diagonal lines.

Understanding distance-time graphs is vital as they are basic tools for interpreting and predicting motion. Frequent practice in reading and interpreting these graphs will improve your proficiency.