How many wavelengths are there now in one pulse?

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SUMMARY

The discussion focuses on calculating the number of wavelengths in a pulse of light emitted by a laser with a frequency of 5.1 x 1014 Hz and a pulse duration of 2.6 x 10-11 s. The wavelength is determined using the formula λ = c/f, where c is the speed of light in a vacuum (approximately 3.0 x 108 m/s). The initial calculation yields a wavelength of approximately 5.88 x 10-7 m, resulting in 1.5 x 103 wavelengths per pulse. When the light enters water, where its speed decreases to 2.3 x 108 m/s, the new wavelength is calculated to be approximately 4.5 x 10-7 m, resulting in 1.17 x 103 wavelengths per pulse.

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Homework Statement


A certain type of laser emits light that has a frequency of 5.1* 10^14 Hz. The light, however, occurs as a series of short pulses, each lasting for a time of 2.6* 10^-11 s. (a) How many wavelengths are there in one pulse? (b) The light enters a pool of water. The frequency of the light remains the same, but the speed of the light slows down to 2.3* 10^8 m/s. How many wavelengths are there now in one pulse?


Homework Equations



lamda= c/f

The Attempt at a Solution


I tried multiplying speed of electromagnetic wave with the time and divided by the freq but the answer is not correct. I am doing it online I just have 1 more chance left. Help!
 
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What is the length (in meters) of the 2.6*10-11s pulse?

What is the wavelength (also in meters)?
 

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