Week #3: Sound Science
- Observe sounds as produced by vibrations
- Recognize some sounds as unpleasant or even dangerous
- Demonstrate multiple ways to produce sound
- Construct and modify devices to create a range of sound characteristics (pitch and loudness/amplitude)
- Measuring, cutting, and combining materials to improve their structural strength
- Leaners discussed examples of sounds that were pleasing, unpleasant, and even harmful.
- Learners observed the relationship between vibrations and sound by using these models:
- Tapping a table hard and soft
- Watching jars of water produce waves when the table was struck
- Comparing the sounds made by tapping tall and short jars and how they changed as water was added to them
- Feeling the front of their voice box while making loud and quiet sounds and varying the pitch from high to low
- Tapping plastic tubes of different lengths
- Comparing the sounds made by tuning forks of different lengths
- Plucking a string held at different lengths
- Learners constructed and modified simple instruments:
- Comb Harmonica
- Plastic straw pan flute
- Rubber band harp
- Hairpin thumb piano
Questions to Discuss
- What are three sounds that are painful to your ears? What are three ways that we can protect our ears from loud sounds?
- How did the vibrations made by your throat change when you made louder noises? How did they change when you sang high or low?
- Did tapping the tables hard make bigger or smaller waves in the water jars? Did it make a difference if there was a little or a lot of water in the jars?
- How did adding water to the jar change the sound it made?
- How did using different sizes of straws affect the sound of they made when you blew across them?
- For your rubber band harp, what was something important to making different sounds with it?
- Why do you think the hairpins made a different sound when taped down on the yogurt tub compared to when it was against the table? Does the length of the hairpin matter for making different sounds?
- Of all the instruments that you made, which one made the sounds you liked best?
Things to Try at Home
- Interview someone who plays a musical instrument. Do they know how it makes sound? Can they explain how they make it louder and quieter or higher and lower sounds?
- Listen through a door using only your ear. Then try again using a glass between your ear and the door. Is it better or worse? Does the size of the glass matter? What if you use a plastic cup instead?
- Many animals use vibrations to communicate or survive. Find out more about how some animals use vibrations. For example:
- elephants use foot stomping to send warnings to other elephants
- mole rats make seismic waves to find their way around underground obstacles
- some snakes use vibration to sense their prey