A rule of thumb for estimating the distance in kilometers between an observer and a lightning stroke is to divide the number of seconds in the interval between the flash and the sound by 3. Discuss whether or not this rule is correct.
I say it is correct because the speed of light is faster than the speed of sound, sound has a delay. (Am I heading in the right direction with this answer.)
you are headed in the right direction.
Light also has a delay, but it is so short that the difference in arrival time is due entirely to the slow speed of sound, which is approximately
wait for it ...
1/3 km/sec!
You are on the right track, but let me explain in more detail.
The rule of thumb you mentioned is based on the fact that light travels much faster than sound. Light travels at approximately 300,000 kilometers per second in a vacuum, while sound travels at around 343 meters per second in dry air.
When we see a flash of lightning, we perceive the light almost immediately because it travels so fast. However, the sound of thunder takes some time to reach our ears, as sound travels at a much slower speed. The time interval between seeing the lightning and hearing the thunder is due to this speed difference.
To estimate the distance to the lightning strike, the rule of thumb suggests dividing the time in seconds between seeing the flash and hearing the thunder by 3. This estimation assumes that the time interval is measured in seconds, which simplifies the calculation.
Since sound travels at approximately 343 meters (or 0.343 kilometers) per second, dividing the time interval by 3 gives us an approximation of the distance in kilometers between the observer and the lightning strike.
It is important to note that this rule of thumb provides only an estimation, as the speed of sound can vary depending on factors such as temperature, humidity, and wind. Additionally, the rule assumes that the lightning strike occurred relatively close to the observer. If the lightning is far away, the accuracy of this estimation will decrease.
In summary, the rule of thumb for estimating the distance in kilometers between an observer and a lightning strike by dividing the time interval between the flash and the sound by 3 is based on the difference in speed between light and sound. While it can provide a rough estimate, it is not a precise method and can be affected by various factors.
Yes, you are heading in the right direction with your answer. The rule of thumb you mentioned is indeed based on the observation that sound travels at a much slower speed than light.
When lightning occurs, the light reaches the observer almost instantly because the speed of light is extremely fast (approximately 299,792 kilometers per second). However, sound travels at a much slower speed, around 343 meters per second (or roughly 1 kilometer in approximately 3 seconds).
By dividing the number of seconds between seeing the flash and hearing the thunder by 3, you can estimate the distance between the observer and the lightning stroke in kilometers. This estimation assumes that the sound and light both originate from the same location, which is generally true for nearby lightning strikes.
However, it is important to note that this rule of thumb provides an approximate estimate and assumes that the speed of sound remains constant. In reality, the speed of sound can vary with factors such as temperature, humidity, and wind. Therefore, this rule should be used as a rough estimate and not as an accurate measurement.