科学素养与生活应用·英语30篇（2）

6 / 30

已读 0 / 30 课

降噪耳机如何制造静音

Active noise-canceling (ANC) headphones use microphones to detect incoming ambient sound waves.
Then, built-in processors generate 'anti-noise' signals—sound waves with opposite phase and equal amplitude.
When original and anti-noise waves meet, they cancel each other through destructive interference.
This works best for low-frequency hums like airplane engines or air conditioners—not sudden speech.
Passive isolation from earcup padding blocks higher frequencies, complementing ANC performance.
Battery power runs the circuitry; turning off ANC extends playback time noticeably.
Some models adapt cancellation in real time based on fit and movement using motion sensors.
While effective, prolonged use at high volumes may still harm hearing—volume limits matter most.

听 → 读 → 学表达 → 懂 → 今天会说这一句 → 跟读录音 → 自己说一句。

Passive isolation from earcup padding blocks higher frequencies, complementing ANC performance. 耳罩垫层提供的被动隔音可阻隔高频声音，从而补充ANC性能。
Active noise-canceling (ANC) headphones use microphones to detect incoming ambient sound waves. 主动降噪（ANC）耳机通过麦克风检测环境声波。
Battery power runs the circuitry; turning off ANC extends playback time noticeably. 电路运行依赖电池供电；关闭ANC可显著延长播放时间。

这篇中文题目最接近哪一句？降噪耳机如何制造静音一次学校运动会的通知一份超市购物清单

课文第一句的意思更接近？主动降噪（ANC）耳机通过麦克风检测环境声波。今天学校放假了。请把窗户打开。

这一课主要在讲什么？（看英文标题） How Noise-Canceling Headphones Create Silence How to cook noodles A maths worksheet

Passive isolation from earcup padding blocks higher frequencies, complementing ANC performance.

Passive isolation from earcup padding blocks higher frequencies, complementing ANC performance.

第一版：录下来、回听、再听标准音。系统打分以后再加。

用今天的表达，自己说一句。

例子：Passive isolation from earcup padding blocks higher frequencies, complementing ANC performance.