In thunderstorm weather, we often see lightning, and it takes a while to hear thunder. Do you know why?

In thunderstorm weather, we often see lightning and then hear thunder for the following reasons:

We need to know the speed of light and sound in the air. The speed of light is very fast, about 300 thousand kilometers per second, while at normal temperature and pressure, the speed of sound is about 340 meters per second. The time required for light to travel in the air is extremely short, almost instantaneous. It takes longer for sound to reach our ears.

In thunderstorm weather, when lightning occurs, visible light and sound (thunder) are generated almost simultaneously. Because the speed of light is much faster than the speed of sound, light will reach our eyes immediately, while sound will take longer to reach our ears. We always see lightning first and then hear thunder.

This phenomenon can also be explained as the difference between the speed of light and the speed of sound. Light travels very fast in the air, but it takes longer for sound to reach our ears. When lightning happens, light will spread to our eyes immediately, while sound will take longer to reach our ears.

The application of light speed and sound speed;

1, the speed of light plays a vital role in communication and measurement technology. In optical fiber communication, the speed of light is used to transmit information. By using high-speed optical pulses, optical fibers can transmit a large amount of data at a very high speed. In measurement, the speed of light can be used to accurately measure length and time. For example, by measuring the propagation time of optical pulses in the medium, the refractive index of the medium can be determined, and then the physical quantities such as length can be calculated.

2. The speed of sound is also widely used in engineering and physics. In architecture and urban planning, the speed of sound is used to determine the characteristics of sound propagation. For example, by measuring the propagation speed of sound waves in building materials, the sound insulation performance can be evaluated. In physical experiments, the measurement of sound velocity is also very important for studying the properties and characteristics of substances.

3. Another application field is aerospace. In the design of high-speed aircraft, the difference between light speed and sound speed is very important for navigation and control. For example, when flying at high speed, pilots need to consider the difference between the speed of light and the speed of sound in order to correctly interpret flight instruments and perform flight tasks.