This experiment, I have to say, seemed normal to me. Maybe because I did this experiment often growing up. Nevertheless, it was in the book so I had to do it. But I won’t complain! An experiment is an experiment.
First off I grabbed three glass bottles from my experiment kit. The first one I filled up with water (I colored it so you could see it), the other one I left empty, and the third bottle I will use in one minute. Taking a spoon, I tapped it to the bottle and then to the other.
It looks like I am laughing there.. its because I was!! I felt kind of silly just standing there tapping the bottles back and forth while my mom takes pictures!
What do you think happened? Well you might think that the bottle made a sound and you would be right! But do you think that they would make the same sound? I encourage you to try and see!! RIGHT NOW! Use your glass cups. It will take two seconds to find out!
What did you notice? Were they the same or different? Different! Why do you think that happened? We will find out in just a minute!
I filled the third bottle half way full with water (and colored it) and put it in between the other two and repeated the process with my spoon.
What kind of sound did the half filled glass make? Is it higher, lower, or in the middle of the others? If you ran to do it yourself, then you know that the sound was in between the other two sounds. The purple bottle high, empty bottle low, green bottle somewhere in the middle.
What if I got many glasses and made a musical scale? That is just what I did.
I did not have 5 glass bottles but these plastic ones worked just fine. I tapped the bottles with the spoon and it didn’t make the same kind of sound with the glass bottles, which is expected. Why? Plastic and Glass are very different materials. Of course they are not going to sound the same. The bottles made a clum sound while the glass make a cling sound. I still enjoyed it though! There is a really cool aspect to these bottles! Have you ever had a bottle of some sort and blew over the top of it? If you haven’t, you are missing a vital part of your childhood. Hours of musical entertainment in your own hands! By blowing air over the top you make the air in the bottle vibrate making an awesome sound. I blew over the bottles and switched from bottle to bottle. I went from green (far right) to yellow (far left) and as I progressed from one to the other the sound lowered! As the liquid lowered so did the sound. But when you tap the bottle, the sound grew higher as the liquid lowered.
What’s happening?
Well when you tap the bottle, it vibrates and that vibration makes the sound. When you add water, the sound is lower. That’s because the water makes the bottle not vibrate as much, thus, lowering the sound. But what about blowing across the top of the bottle? Why was it opposite?
Well, I am going to leave that for you to find out! I can’t hog all of the fun!
Afterwards, Mom suggested to me to ramp it up a little….. I pulled out the vacuum.
Fast moving air and bottles with water……… Let it begin!
The vacuum made the bottles sing like never before! It was fun. Although the yellow bottle wanted to join the dust bunnies, it worked perfectly.
Now for the WOW-rating. I have to be honest, I’d give it a 2- Fun to do just once. But the vacuum made it much more interesting!
