What term describes the increase of speed or velocity?

• A. Instantaneous
• B. Ascend
• C. Acceleration
• D. Relative Change

Answer: (C)

Acceleration is the rate at which velocity changes over time. It describes how quickly something speeds up, slows down, or changes direction, since velocity includes both speed and direction. When velocity increases, acceleration is positive in the straight-line case, and in general any change in velocity is captured by acceleration. For example, going from 10 m/s to 15 m/s in 1 second yields an acceleration of 5 m/s^2. If the motion involves turning without a speed change, the velocity vector still changes, so there is acceleration. The other terms don’t fit: instantaneous refers to a single moment, not the rate of change; ascend isn’t the physics term for velocity change; and relative change is a general math idea, not the standard description of how velocity evolves.