Displacement 

Displacement, in meters, is calculated by finding the area under a velocity-time graph. The displacement graph is a parabola when the velocity-time graph is a straight line.

Note:  the area (integral) on the velocity graph gives the displacement (change in position) only. The displacement at zero time on the position-time graph has been set to zero in this example.

In calculus terms, the constant of integration may be set to any appropriate value (boundary condition).

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