Let’s see how you did! If you didn’t get a few of these, don’t let it stress you out – it just means you need to play with more experiments in this area. We’re all works in progress, and we have our entire lifetime to puzzle together the mysteries of the universe!
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Answers:
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1. Our antennae are our ears, eyes, and skin.
2. Antennae pick up energy. Our eyes, ears and skin all pick up energy. Our brain then interprets the energy as light, sound or heat. By the way, you may be asking, “What about the nose? Is our nose an antenna”? Not in my opinion. Molecules have to come into the nose and land on smell sensors to register as a smell. Noses detect matter (molecules), not energy.
3. Our two ears, plus our brain allow us to be fairly accurate at knowing where sounds are coming from. The sound will hit one ear before hitting the other and our brain can do the math and figure out which direction.
Section Two:
1. Longitudinal. The waves travel with the medium.
2. Solids
3. The particles are close together. The closer the particles the faster sound travels.
4. A cold day, since the molecules are closer together.
5. Light is much faster.
6. Sound travels 1000 ft/sec, so that firework is 1000 feet away.
7. Take 10 seconds and divide it by 5. So the lightning is 2 miles away.
Section Three:
1. Energy is the ability to move something against a force. In the case of sound, molecules are moving.
2. Vibrations. No vibration, no sound.
3. Longitudinal wave.
4. Frequency determines the pitch of the sound. The higher the frequency, the higher the pitch. The lower the frequency the lower the pitch.
5. The higher the amplitude of the wave, the louder the sound is. Higher amplitude means more energy which means louder sound.
Section Four:
1. Something vibrating causes sound. The sound waves are carried from the vibrating thing to your ears by longitudinal waves.
2. Everything! Couches, clams, mobile homes, they all vibrate.
3. The frequency something tends to vibrate at.
4. They make different noises because they vibrate at their natural frequency. When they are plunked the frequency that they vibrate at causes the sound wave that we hear.
5. Size, weight, and the material of an object determine its natural frequency.
6. Resonance is when something is vibrating at the same natural frequency as something else and causes that something else to vibrate as well.
7. No. Our ears have a natural frequency between 20-20,000 Hz. They will not vibrate at frequencies outside that range so we cannot hear something that vibrates at 30,000 Hz. Our ears can only be resonated by vibrations between 20-20,000 Hz.
8. If something continues to be resonated by something else, the thing that’s being resonated will vibrate more and more. Eventually, unless the energy is stopped or the vibration is slowed, the object being resonated may break. This is how singers can break wine glasses. They can hit a note that resonates the wine glass. As they keep singing, the wine glass vibrates more and more until it shatters!
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