Problem: Consider a single photon with a wavelength of λ, a frequency of ν, and an energy of E. What is the wavelength, frequency, and energy of a pulse of light containing 100 of these photons? Please explain all steps.

Given: 100 photons

Recall that the energy of 1 photon:

$\boxed{\mathbf{E}\mathbf{=}\mathbf{hv}} \left(1\right)$

where:

h = Planck’s constant (6.626 × 10^–34 J • s)
v = frequency (in s^–1)

Wavelength and frequency of light are connected using the following equation:

$\boxed{\mathbf{\lambda }\mathbf{=}\frac{\mathbf{c}}{\mathbf{v}}} \left(2\right)$

where:
c = speed of light (3.0 × 10⁸ m/s)

Therefore, energy can also be expressed as: