PITTSBURGH (KDKA) — Without light, we can’t have sight. We see objects because of how light interacts with those objects, our eyes pick up that light, and our brains interpret it.

This seems rather basic, but how light interacts with different things can be very, very interesting. Light can bounce off things. That is called reflection.

(Photo Credit: KDKA Weather Center)

(Photo Credit: KDKA Weather Center)

Light can be absorbed by objects. This is what happens with darker surfaces.

(Photo Credit: KDKA Weather Center)

(Photo Credit: KDKA Weather Center)

Light can also pass through some things but is bent as it does so. This transmission is called refraction.

(Photo Credit KDKA Weather Center)

(Photo Credit KDKA Weather Center)

Reflection and refraction are what we are going to focus on today using these beakers. Reflection and refraction are also why we can see clear things like those beakers.

Some of the light reflects off the glass. The light that passes through moves at different speeds through different, transparent materials and substances like the glass beaker and the air in the glass beaker.

Today we are going to make the small beaker disappear with this idea of reflection and refraction and a substance called Vegetable Glycerin. I like to call it “invisibility goop”. You will see why very soon.

For this experiment, we are going to put a beaker in a beaker. You can see both because the light is bent as the light changes speeds while moving through the air and the glass of the beakers. This allows our eyes to see them.

When we add the invisibility goop into the smaller beaker on the inside, not much changes…yet.

Now we are going to fill the bigger beaker with the goop. Watch what happens to the beaker on the inside.

It seems to have disappeared. It is still there. It is just invisible.

This invisibility goop reflects and refracts light almost exactly like the glass does. This means that light is traveling at pretty much the same speed through the goop as it does the glass, preventing more reflection and refraction…making it appear to disappear!