An object whose velocity changes by the same amount each second is experiencing constant acceleration.

Here's why:

* Acceleration is the rate of change of velocity.

* Constant acceleration means the velocity changes at a steady rate.

* If the velocity changes by the same amount every second, this indicates a consistent rate of change, which is constant acceleration.

Examples of constant acceleration:

* A ball falling freely under gravity experiences constant acceleration due to the Earth's gravitational pull.

* A car accelerating from rest at a steady rate is also experiencing constant acceleration.