def get_photon_energy(wavelengths):
    """
    computes the energy of the photon of a given wavelength
    :param wavelengths: [m]
    :return: J = W*s
    """
    plank_constant = 6.62606957 * 10**-34  # J*s
    speed_of_light = 299792458  # m*s^-1
    nu = speed_of_light / wavelengths  # s^-1
    E = plank_constant * nu  # J = W*s
    return E