1. Sound Is Measured in a Unit Called Watts. Have You Seen the Word Watts Before? in What

Name: David Macmorine Contact Info: [email protected] Date:11-Jul-14

Lesson Title: What is Sound? Unit #: Lesson #: Activity #: Worksheet: b Activity Title: What is Sound? 5 1 2 Worksheet Title: Measuring Sound

Name Date Period

1. Sound is measured in a unit called Watts. Have you seen the word Watts before? In what situation?

2. A Watt is a unit of ‘energy flow’ defined as a Joule per second. What is a Joule? If you don’t know, look it up on the internet.

3. Not everyone has the same ability to hear, so the level chosen as the least amount of energy that someone can hear is taken as 10-12 Watts per meter2. Write out 10-12 as a decimal number.

4. If you were to study sound, would you like to write down numbers like #3 all the time? That is why scientists came up with the decibel scale. The definition of decibel scale is –

-12 2 -12 Where I0 = 10 watts per meter . If I = 10 calculate the dB of this sound intensity.

5. Examine the following table where the value of the sound is given in Watt per meter2 –

Calculate the dB of each of the sounds. Look for a pattern.

6. How many times louder is loud music than soft music?