Answer
(a) The laser pulse is in the ultraviolet part of the EM spectrum.
(b) A single pulse is $0.30~cm$ long.
(c) There are $1.55\times 10^4$ wavelengths in each pulse.
Work Step by Step
(a) The wavelength is $193~nm$, which is slightly shorter than the shortest wavelength of visible light. The laser pulse is in the ultraviolet part of the EM spectrum.
(b) We can find the distance an EM wave travels in a time of $10.0~ps$:
$d = c~t$
$d = (3.0\times 10^8~m/s)(10.0\times 10^{-12}~s)$
$d = 3.0\times 10^{-3}~m$
$d = 0.30~cm$
A single pulse is $0.30~cm$ long.
(c) The wavelength is $193~nm$. We can find the number of wavelengths in one pulse:
$\frac{3.0\times 10^{-3}~m}{193\times 10^{-9}~m} = 1.55\times 10^4$
There are $1.55\times 10^4$ wavelengths in each pulse.
