You're asking for a bit of a contradiction here! Let's break down why:

* Uniform Motion: This means an object is moving at a constant speed in a straight line. The velocity doesn't change.

* Velocity Changing at a Rate: This implies acceleration, meaning the object is speeding up, slowing down, or changing direction.

So, there's no example of uniform motion in a straight line where the velocity is changing at a rate.

Here's an example of what you're probably thinking about:

Imagine a car driving down a straight road. If the car is accelerating (speeding up or slowing down), its motion is not uniform. Even though the car is moving in a straight line, its velocity is changing.

Here are some examples of motion where the velocity is changing:

* A ball falling from a height: The ball's velocity increases due to gravity.

* A car braking to a stop: The car's velocity decreases until it reaches zero.

* A rocket launching into space: The rocket's velocity rapidly increases as it accelerates.

Let me know if you have any other physics questions!