How many wavelengths are there now in one pulse?

In summary, the conversation discusses a certain type of laser that emits light with a frequency of 5.1*10^14 Hz in short pulses lasting for 2.6*10^-11 s. The question is asked about the number of wavelengths in one pulse, and the answer is found by using the equation lamda= c/f. The second part of the conversation involves the light entering a pool of water, where the frequency remains the same but the speed of light slows down to 2.3*10^8 m/s. The question is asked again about the number of wavelengths in one pulse, and the answer is found by using the same equation with the new speed and frequency values.
  • #1
ravsau
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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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  • #2
Welcome to physics forums.

What is the length (in meters) of the 2.6*10-11s pulse?

What is the wavelength (also in meters)?
 

Related to How many wavelengths are there now in one pulse?

1. What is the definition of a wavelength?

A wavelength is the distance between two consecutive peaks or troughs in a wave. It is typically measured in meters.

2. How is the number of wavelengths in a pulse determined?

The number of wavelengths in a pulse is determined by dividing the length of the pulse by the wavelength. This can also be calculated by measuring the time between two consecutive peaks or troughs and dividing by the period of the wave.

3. Does the number of wavelengths in a pulse change over time?

No, the number of wavelengths in a pulse remains constant. However, the frequency of the pulse may change, which can affect the wavelength.

4. How does the medium through which a wave travels affect the number of wavelengths in a pulse?

The medium does not affect the number of wavelengths in a pulse, but it does affect the speed of the wave, which in turn can affect the wavelength.

5. Can the number of wavelengths in a pulse be infinite?

No, the number of wavelengths in a pulse is limited by the length of the pulse and the wavelength of the wave. It cannot be infinite, but it can be very large depending on the length of the pulse and the wavelength.

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