When light waves strike a blue object, the object absorbs all colors of light except for blue light. The blue light is reflected back to our eyes, which is why we see the object as blue.

Here's a more detailed explanation:

* Light is made up of a spectrum of colors. This spectrum includes all the colors that we can see, as well as some colors that we can't see, such as ultraviolet and infrared light.

* When light waves strike an object, some of the light waves are absorbed and some are reflected. The color of an object depends on which light waves are absorbed and which are reflected.

* In the case of a blue object, the object absorbs all colors of light except for blue light. The blue light is reflected back to our eyes, which is why we see the object as blue.