Speed/Velocity Graphs

Understanding Speed and Velocity

Speed and velocity are measures of how fast something is moving. Speed is a scalar quantity, meaning it only has magnitude, while velocity is a vector quantity, meaning it has both magnitude and direction.

For example:

• Speed: 60 km/h
• Velocity: 60 km/h north

Graphs of Motion

Graphs can help us understand motion by showing how distance or displacement changes over time.

• Distance-Time Graph: Shows how far an object travels over time.
• Displacement-Time Graph: Shows how an object's position changes over time.

Interpreting Speed/Velocity from Graphs

To determine speed or velocity from a graph, we look at the slope (gradient) of the line:

• Speed: Calculated from the slope of a distance-time graph.
• Velocity: Calculated from the slope of a displacement-time graph.

Calculating Speed and Velocity

The formula for speed and velocity is:

$$\text{Speed} = \frac{\text{Distance}}{\text{Time}}$$

$$\text{Velocity} = \frac{\text{Displacement}}{\text{Time}}$$

Instantaneous Speed/Velocity

Instantaneous speed or velocity is the speed or velocity of an object at a specific moment in time. On a graph, it is represented by the slope of the tangent to the curve at a given point.