I just want to talk to all of you
about "The position and wavelength are mutually uncertain to degree dx dk ~ 1. For example, suppose we attempt to measure the wavelength of a classical wave such as water wave, we can do it by measuring the distance between two adjacent wave crest. It is still ok, But! if the wave is very short pulse with only one wave crest. Measuring wavelength is very difficult!, and we are likely to make a large error perhaps of the order of one wavelength. Back to The wave extends over N cycles, so that dx ~ N lamda. Now we can determine lamda with greater precision

Question

I just want to talk to all of you
 about "The position and wavelength are mutually uncertain to degree dx dk ~ 1. For example, suppose we attempt to measure the wavelength of a classical wave such as water wave, we can do it by measuring the distance between two adjacent wave crest. It is still ok, But! if the wave is very short pulse with only one wave crest. Measuring wavelength is very difficult!, and we are likely to make a large error perhaps of the order of one wavelength. Back to The wave extends over N cycles, so that dx ~ N lamda. Now we can determine lamda with greater precision

anonymous · Answer

But ! counting the number of wavelength in dx we still may make an error of the order of one wavelength..,

anonymous · Answer

How do I resolve the error??