Measuring Speed from a Curved Distance-Time Graph
The gradient of a distance-time graph represents the speed of an object. If the object is accelerating then its distance-time graph will be curved, but you can still use a tangent to calculate its speed.
Not to be confused with distance-time graphs, these show the objects velocity with time. Remember that:
The gradient is equal to its acceleration
The area under the line is equal to its displacement
Velocity-Time Graphs: Example A
The skill in answering questions like this lies in interpreting the graph and reading the correct data.
Velocity-Time Graphs: Example B
This uses the same data as the previous example, but now we use it in a different way. Take the time to split up the area under the line into simpler shapes and then the maths is easy.
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