A position-time diagram (\(x\)-\(t\) diagram) during an accelerated motion of an object shows the relationship between the current position \(x\) of the object at time \(t\). During accelerated motion, the velocity (slope of the \(x(t)\) function) of the object changes over time.
The slope of the curve in the position-time diagram indicates the momentary velocity \(v(t)\) of the object. The steeper the \(x(t)\)-curve, the faster the movement is at this point in time. A straight line in the diagram means that the velocity is constant and there is no acceleration.
- If the acceleration of the object is positive: \(a > 0 \), then the velocity of the object increases with time.
- If the acceleration of the object is negative: \(a < 0 \), then the velocity of the object decreases with time. The object comes to a stop at a certain point in time. At this point, both acceleration and velocity are zero.