Change in velocity is the rate at which an object's velocity changes over a period of time. It is typically measured in meters per second squared (m/s^2).
To calculate change in velocity on an acceleration vs time graph, you can find the slope of the line. The slope represents the rate of change, so the steeper the slope, the greater the acceleration and the larger the change in velocity.
A positive slope on an acceleration vs time graph indicates that the object is accelerating in the positive direction. This means that its velocity is increasing over time.
A horizontal line on an acceleration vs time graph indicates that the object is not accelerating, and therefore there is no change in velocity. This could mean that the object is either at rest or moving at a constant velocity.
To find the change in velocity at a specific time on an acceleration vs time graph, you can draw a tangent line at that point and calculate the slope of the tangent line. This slope represents the acceleration at that specific time, which can then be used to find the change in velocity using the formula: change in velocity = acceleration x time.