공통영어1 미래엔 김성연 3과 빈칸문제

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

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

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

What is the scientific principle ____ this achievement?

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

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

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

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

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

There are two types of ____: constructive and destructive.

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

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

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

____ the headphones are microphones and noise-cancelling circuitry.

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

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

This cancels out the unwanted sound even in noisy surroundings, so you can hear the music sound clearly ____ turning up the volume.

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

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

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

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

Noise-cancelling ____ is not only used in music devices.

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

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

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

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

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

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

Thanks to noise-cancelling devices, it is possible for drivers to focus on driving ____ being disturbed by distracting noises.

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

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

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