If the velocity-time graph is curved, the acceleration can be found by calculating the gradient of a tangent to the curve.

This is the line which is tangent to the velocity curve at the 1 s mark. Its slope is visibly less than 0.5 m/s. By measuring the slopes of the tangent lines to the curve at every second during the ...

If the velocity-time graph is curved, the acceleration can be found by calculating the gradient of a tangent to the curve.