Sept 14th: Lessons 3,4&5

This week’s experiments are all about sound and how it works.

In lesson 3: Sound moves through the air as invisible waves. When you sing, the pitch can be high or low. When you sing high, the waves are more condensed than when you sing low. Frequency is a measure of how many sound waves hit your ear per second.  One thing that determines the pitch on a musical instrument is the thickness of the instrument’s strings. 

Lesson 4: Volume is the height of the waves. A good example of what this looks like is the waves coming in on a beach. The high waves of sound are louder, lower waves are softer. The top of the wave is called a crest, and the lowest part is a trough.

Lesson 5: Sound travelers in air, sort of like wind, and they hit your ear and then you hear them. Sound moves in waves. If a sound wave is moving slowly, it makes a low pitch, and if it is moving quickly, then it’s a high pitch. Frequency is how many sound waves hit your ear per second. If you are singing loud, the waves are huge, but if you are singing softly, they would be very small. When a musician is tuning their instrument, they tighten or loosen the strings, making the waves become slightly higher or lower in pitch. When you pluck a string to make a sound, the pitch it makes changes depending on how close to the end you pluck it.  When you pluck something hard, it travels a great distance from its resting spot, but when you pluck it softly, it might not wiggle very much at all. The harder you pluck, the larger the waves. If it is a high pitch, the waves come in fast frequency, and if it is a low pitch, they come in slow frequency.