공통영어1 미래엔 김성연 3과 변형문제

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

Rarely do people want to put up with a lot of ____ because it can be unpleasant and distracting.

Fortunately, scientists have ____ noise-cancelling technology, which is now being used across various fields to reduce unwanted noise.

____ is the scientific principle behind this achievement?

To understand this, let’s examine ____ sound travels.

The ____ of Sound Waves and Interference

Sound is produced through vibrations that occur from a sound source, when the strings of a guitar are ____, for instance.

The vibrations of the sound source ____ the air to vibrate and the sound to travel as waves, similar to the ripples created in a lake when you throw a stone.

When these sound waves reach our ears, the brain ____ them as sound.

Just as different ripples in water might overlap if you throw two stones, sound waves can also interfere with each other when they ____.

There are ____ types of interference: constructive and destructive.

Constructive interference occurs when the peaks of two waves overlap, resulting in a ____ wave and a louder sound.

Destructive interference, on the other hand, occurs when a ____ of one wave overlaps with a valley of another wave, so they cancel each other out and produce a quieter sound, or no sound at all.

The Science ____ Noise-Cancelling Headphones

____ interference is used in the noise-cancelling feature of headphones when we listen to music.

Inside the headphones are microphones and ____ circuitry.

The microphones pick up ____ from the outside, and the circuitry analyzes them to produce opposite sound waves.

For example, if outside noise has a value of +1, the circuitry will generate an opposite noise of –1 and ____ it to the speakers.

This cancels out the unwanted sound even in noisy surroundings, so you can hear the music sound clearly without turning up the ____.

However, it is not easy to ____ eliminate external noise with this technology.

To achieve full noise cancellation, the circuitry must convert the noise into digital data and ____ transmit the opposite sound to the speakers as soon as the noise reaches the microphones.

____, this noise-cancellation technology is effective for predictable sounds like those of car engines and subways that occur regularly or over a period of time.

However, it’s relatively less effective for inconsistent sounds such as those of people talking close to ____.

____ technology is not only used in music devices.

Other fields also take advantage of this ____, such as ticket offices at tourist attractions which are often very noisy.

Microphones are installed in ticket ____ to detect external noise, and an opposite sound wave is generated and transmitted through a speaker, enabling the ticket agent to hear the customer’s voice clearly.

Another area in which this technology is used is drive-through fast-food restaurants and coffee ____.

They use noise-cancelling headsets to improve communication between employees and customers by eliminating ____ noise.

These noise-cancelling headsets help drive-through ____ take orders accurately.

The same technology is also used for cars, whose ____ systems generate waves to cancel out unpleasant sounds such as engine, wind, and road noise.

Thanks to noise-cancelling ____, it is possible for drivers to focus on driving without being disturbed by distracting noises.

As technology advances, many people ____ it will solve various social issues caused by noise pollution.

A common source of ____ problems is noisy neighbors, as the noise they make can lead to conflict among residents.

____ technology can help address these problems by reducing unwanted disturbances, allowing people to lead more peaceful and healthier lives.