Question

pulsed lasers are used for science and medicine produce very brief bursts of electromagnetic energy. a) if the laser light wavelength is 1062 nm and the pulse lasts for 38 ps, how many wavelengths are found within the laser pulse? b) how brief would the pulse need to be to fit only one wavelength?

Answer 1

To answer your question:

a) The formula to calculate the number of wavelengths within a laser pulse is:

number of wavelengths = pulse duration / wavelength

Plugging in the values given in the question, we get:

number of wavelengths = 38 ps / 1062 nm

Converting picoseconds to seconds and nanometers to meters, we get:

number of wavelengths = 38 x 10^-12 s / 1062 x 10^-9 m

number of wavelengths = 0.0358

Therefore, there are approximately 0.0358 wavelengths within the laser pulse.

b) To fit only one wavelength, the pulse duration would need to be equal to the wavelength. The formula to calculate the pulse duration is:

pulse duration = wavelength

Plugging in the value given in the question, we get:

pulse duration = 1062 nm

Converting nanometers to picoseconds using the speed of light ©, we get:

pulse duration = wavelength / c

pulse duration = 1062 x 10^-9 m / 3 x 10^8 m/s

pulse duration = 3.54 x 10^-12 s

Therefore, the pulse would need to be approximately 3.54 ps long to fit only one wavelength.

I hope this helps