Variable-mass system events. The following derivation is for a body that is gaining mass (accretion). A body of time-varying mass "m" moves at a velocity v at an initial time "t". In the same instant, a particle of mass dm moves with velocity u. The initial momentum can be written as Now at a time "t" + d"t", let both the main body and the particle accrete into a body of velocity v + dv. Thus the new momentum of the system can be written as Since d"m"dv is the product of two small values, it can be ignored, meaning during d"t"
Velocity (software development) more like the concept of directionless “speed” from physics. A third problem with velocity is that it is often misused as a measure of efficiency or team performance. Velocity is a metric of work done, not efficiency. Velocity can be increased by working overtime or adding team members, neither of which necessarily increase efficiency or performance. In summary, velocity is a problematic metric because it is easy to manipulate and often misused as an indicator of efficiency. Velocity (software development) Velocity is a metric for work done, which is often used in agile software development. Measuring velocity is sometimes called