Doppler effect

简明释义

多普勒效应

英英释义

例句

1.When an ambulance passes by, the change in pitch of its siren is a clear demonstration of the Doppler effect (多普勒效应).

当救护车经过时，它的警报音调变化清晰地展示了Doppler effect（多普勒效应）。

2.Astronomers use the Doppler effect (多普勒效应) to determine whether stars are moving toward or away from Earth.

天文学家利用Doppler effect（多普勒效应）来判断恒星是朝向地球移动还是远离地球。

3.The Doppler effect (多普勒效应) explains why the sound of a train changes as it approaches and then passes.

当火车接近然后经过时，Doppler effect（多普勒效应）解释了声音为何会变化。

4.In medical imaging, the Doppler effect (多普勒效应) is used to measure blood flow.

在医学成像中，Doppler effect（多普勒效应）用于测量血流。

5.The Doppler effect (多普勒效应) can also be observed with light waves, not just sound waves.

光波也可以观察到Doppler effect（多普勒效应），而不仅仅是声波。

作文

The Doppler effect is a fascinating phenomenon that occurs when there is a relative motion between a source of waves and an observer. This effect is most commonly associated with sound waves, but it can also be observed in light waves. The basic principle behind the Doppler effect is that as the source of the waves moves closer to the observer, the waves are compressed, leading to a higher frequency or pitch. Conversely, as the source moves away, the waves are stretched, resulting in a lower frequency or pitch. This principle has numerous applications in various fields, including astronomy, radar technology, and even medical imaging.One of the most common examples of the Doppler effect can be heard when an ambulance passes by. As the ambulance approaches, the sound of its siren is at a higher pitch. However, as it moves away, the pitch decreases. This change in frequency is not due to any alteration in the siren itself, but rather due to the relative motion between the ambulance and the observer. This practical demonstration of the Doppler effect illustrates how our perception of sound can change based on movement.In astronomy, the Doppler effect plays a crucial role in understanding the universe. By observing the light from distant stars and galaxies, astronomers can determine whether these celestial bodies are moving towards us or away from us. When a star moves away, its light shifts towards the red end of the spectrum, known as redshift. Conversely, when it moves towards us, the light shifts towards the blue end, known as blueshift. This information is vital for studying the expansion of the universe and the movement of galaxies.Moreover, the Doppler effect is instrumental in radar technology. Police use radar guns to measure the speed of vehicles on the road. The radar gun emits radio waves that bounce off a moving vehicle. By analyzing the frequency shift of the reflected waves, officers can calculate the speed of the vehicle. This application of the Doppler effect is essential for maintaining traffic safety and enforcing speed limits.In the field of medicine, the Doppler effect is utilized in ultrasound imaging. Medical professionals use Doppler ultrasound to assess blood flow in patients. By observing the frequency changes in the sound waves reflected off moving blood cells, doctors can diagnose various conditions, such as blood clots or heart problems. This non-invasive technique has revolutionized the way we monitor and treat cardiovascular health.In conclusion, the Doppler effect is not just an abstract scientific concept; it is a practical phenomenon that affects our daily lives in numerous ways. From the sounds we hear to the light we observe in the cosmos, the Doppler effect provides valuable insights into the behavior of waves in motion. Understanding this effect enhances our comprehension of the natural world and opens doors to innovative technologies that improve our quality of life. As we continue to explore the intricacies of physics, the Doppler effect remains a key concept that bridges the gap between theory and real-world application.

多普勒效应是一个迷人的现象，当波源与观察者之间存在相对运动时就会发生这种现象。这个效应通常与声波相关，但在光波中也可以观察到。多普勒效应的基本原理是，当波源靠近观察者时，波被压缩，导致频率或音调升高。相反，当波源远离时，波被拉伸，导致频率或音调降低。这个原理在各个领域都有许多应用，包括天文学、雷达技术，甚至医学成像。多普勒效应的一个常见例子是当救护车经过时可以听到的声音。当救护车接近时，警报声的音调较高。然而，当它远离时，音调会降低。这种频率的变化并不是由于警报本身的改变，而是由于救护车与观察者之间的相对运动。这个多普勒效应的实际演示说明了我们对声音的感知如何因运动而变化。在天文学中，多普勒效应在理解宇宙方面起着至关重要的作用。通过观察来自遥远恒星和星系的光，天文学家可以确定这些天体是朝向我们移动还是远离我们。当一颗星星远离时，它的光线向光谱的红色端偏移，称为红移。相反，当它朝向我们时，光线向蓝色端偏移，称为蓝移。这些信息对于研究宇宙的膨胀和星系的运动至关重要。此外，多普勒效应在雷达技术中也发挥着重要作用。警察使用雷达枪来测量道路上车辆的速度。雷达枪发出无线电波，这些波在移动的车辆上反射。通过分析反射波的频率变化，执法人员可以计算出车辆的速度。多普勒效应的这个应用对于维护交通安全和执行限速至关重要。在医学领域，多普勒效应被用于超声成像。医疗专业人员使用多普勒超声来评估患者的血流。通过观察反射在移动血细胞上的声波的频率变化，医生可以诊断各种病症，如血栓或心脏问题。这种非侵入性技术彻底改变了我们监测和治疗心血管健康的方式。总之，多普勒效应不仅仅是一个抽象的科学概念；它是一个实用现象，在许多方面影响着我们的日常生活。从我们听到的声音到我们在宇宙中观察到的光，多普勒效应提供了关于运动波行为的宝贵见解。理解这一效应增强了我们对自然世界的理解，并为改善我们生活质量的创新技术开辟了道路。随着我们继续探索物理学的复杂性，多普勒效应仍然是一个关键概念，架起了理论与现实应用之间的桥梁。