Hello everyone!
I hope that you had a great spring break. 2 weeks must be nice but hard to get back to learning.
Today you were supposed to learn about resonance. This is a complicated subject but is very cool! Resonance phenomena can help describe many different things that we observe everyday. First we have to realize that everyday objects have a special frequency that they vibrate at. This is called the natural frequency of an object. It is just the amount of vibrations that an object will have if it is forced to vibrate. Any easy way to think of it is imagine if I was dangling my keys. You would immediately know that it was my keys that were making the sound. The reason you know is because keys always make the same sound - because they vibrate at their natural frequency. Now resonance occurs when another sound or vibration is acting at the exact same frequency as the natural frequency of the object. This will cause the object to vibrate without touching it. Really, the sound waves coming in push on the object at the same frequency that it "likes" to vibrate at. So this sound waves pushes and pulls when the compression and rarefaction regions strike it. When it pushes and pulls, the object begins to vibrate at the same frequency. We call this resonance. Ms. Yoshizumi showed you a cool demonstration of this. If you didn't think it was cool something is wrong with you!!! Really!
So....here are some answers to your questions
3rd: An opera singers voice can break a wine glass through resonance. If she sings at the exact same frequency as the frequency that the wine glass likes to vibrate at (its natural frequency) then it will start to vibrate. The vibrations become so large (big amplitude) that the glass cannot withstand the changes and it shatters. Resonance!! Why is the sky blue??? The sky is blue because the molecules that make up the sky (mostly nitrogen and carbon molecules plus water) are the exact right size that they scatter the photons coming from the sun that are blue and violet. The other photons are absorbed or reflected so we do not see them. I have a very cool demonstration to show this. Perhaps I will get the chance to let you see it. Why is the sky blue!!!
4th: The highest and lowest frequency is a vague question. I wish that I was there to hear you ask it. Do you mean that humans can hear? If so, many humans hear on the range of 20 - 20,00o Hz. That means that anything that vibrates with these frequencies, we can hear. Have you heard of a dog whistle? These whistles have a very high frequency. Too high for most people to hear, but dogs can hear them. I have heard of some people that claim to be able to hear them, too. What about you? Do you mean the frequency that light waves have? Light waves have very high frequencies. They are caused when charges (we haven't learned about this) like electrons vibrate very fast. But, alas, I don't know if I am answering your question.
5th: Vibrations sound cool because the parts in your ear are exactly the right shape and size so that they vibrate when sounds come near them. Music is a vibration that many of us love. Although some people's taste in music we may not find pleasing. I for one, like country music and punk rock. What kind do you like? A pendulum can start swinging all by itself because of resonance. It makes a sound -even though you cannot hear it - and this sound's compression and rarefaction regions push and pull on the pendulum to make it move. It is kinda like when you are on a swing. If you move your legs just right, you will start to swing higher and higher. Do you know what I am talking about?
Thanks for your questions. I am stuck in Kazakhstan and do not know when they will let me go ( if ever). I sure miss my dog, my mom, my sister, her kids, and even Uncle Punk.
Please continue to learn and be NICE to Ms. Yoshizumi for heaven's sake!!