G1 L3.Tuning Out: The Science of Noise-Cancellation1(p.61-62)

Front

Which is the better environment for studying: a noisy place or a quiet place?

A: a quiet place

B: a noisy place

Back

A: A quiet place is better for studying.

Front

What technology has been invented to reduce unwanted noise?

( ) - ( ) ( )

Back

Noise-cancelling technology.

Front

What is the scientific principle behind noise-cancelling technology?

Sound ( ) and ( )

Back

It involves understanding how sound travels and the principles of sound waves and interference.

Front

How is sound produced?

• -Through ( ) from a sound source

Back

Sound is produced through vibrations from a sound source.

Front

What happens when sound waves reach our ears?

• - The ( ) interprets them as ( )

Back

The brain interprets them as sound.

Front

What are the two types of interference in sound waves?

Back

Constructive interference and destructive interference.

Front

What occurs during constructive interference?

• - The ( ) of two waves ( )

• and make a ( bigger/smaller ) wave and ( quieter/ louder) sound

Back

The peaks of two waves overlap, resulting in a bigger wave and a louder sound.

Front

What occurs during destructive interference?

• - A ( ) of one wave overlaps with a ( ) of another wave.

Back

A peak of one wave overlaps with a valley of another wave, canceling each other out and producing a quieter sound or no sound at all.

Front

What is the speed of sound in air at room temperature?

1. 1. about 252 m/s

2. 2. about 343 m/s

3. 3. about 958 m/s

Back

2. 2. about 343 meters per second.

Front

What is the unit of measurement for sound intensity?

소리 측정의 단위는?

1. 1. J

2. 2. kg

3. 3. dB

Back

Decibel (dB).