You're right to be confused! An object cannot accelerate if it's moving at a constant speed. Here's why:

* Acceleration is the rate of change of velocity.

* Velocity is a combination of speed and direction.

So, if an object is moving at a constant speed but changing direction (like a car going around a curve), it is accelerating because its velocity is changing. If an object is moving at a constant speed in a straight line, its velocity is constant and it is not accelerating.

Here's a simple example:

Imagine a car driving down a straight road at 60 mph. If it continues at 60 mph in a straight line, it's moving at a constant speed and not accelerating.

But, if the car turns a corner, even if it maintains a speed of 60 mph, it is accelerating because its direction is changing.

Key point: Acceleration is about changes in velocity, not just changes in speed.