Solving Speed and Acceleration Problems

Distance-Time Graph

• The gradient in a distance-time graph represents the speed of an object; a steeper gradient indicates a higher speed.
• If the gradient is a curve, it indicates a change in speed, meaning the object is accelerating or decelerating rather than moving at a constant speed.

Speed-Time Graph

• The gradient in a speed-time graph represents acceleration; a positive gradient indicates increasing speed, while a negative gradient indicates decreasing speed.

Graph Shapes Under Different Conditions

• An object moving in the presence of air resistance typically shows a curve in the speed-time graph, as it accelerates initially and then levels off, indicating a terminal velocity.
• An object moving in the absence of air resistance shows a linear graph in the speed-time representation, indicating constant acceleration until it stops accelerating.