+

Did You Hear That?

By Andrew Cobb & Ionut Albu

+The “Screaming” Balloon

What made the balloon “scream”?

Key Question: What is sound, how is it made and

transferred?

+Tuning Fork & Ping Pong Ball

DO NOT HIT THE TUNING FORK ON YOUR DESKS. ONLY USE THE PALM OF YOUR HAND.

One group member hit the tuning fork, another touch the ping pong ball to the tuning fork

Be sure to make a prediction before you start the experiment

Let each member of the group give it a try

+Tuning Fork & Water

Hit the tuning fork (again only using your palm) and place it in the water

Be sure to only put the tuning fork in about half an inch

Don’t touch the tuning fork to the side of the glass, this will mess up your results

+The “Clucking Chicken”

Be careful with how you pull on the string

Try it first without wetting the sponge, holding the cup

Then try it with a wet sponge, holding the cup

Then, while also using a wet sponge try it holding the string and not the cup

+Sound Wave

Wavelength

Amplitude

+Wavelength and Frequency

Short Wavelength

Long Wavelength

+Pitch

Pitch makes a sound “high” or “low” Depends on frequency

Objects with less matter vibrate faster Faster vibration = Higher frequency

Higher Frequency = Higher pitch

Objects can vibrate or the air inside of them, this affects the kind of pitch you get.

+Predict Pitches for each Bottle:Struck

✓

✓

✓

+Predict Pitches for each Bottle:Blown

✓

✓

✓

+Review

Sounds are made by vibrations. travel as waves.

Waves have energy. are measured from peak to peak or trough to trough.

Frequency measures the number of vibrations in one second.

Pitch How “high” or “low” a sound is and depends on frequency