E = hf
where h is Planck's constant (h = 6.626 x 10^-34 J s) and f is the frequency of the light.
Plugging in the values, we get:
E = 6.626 x 10^-34 J s * 4 x 10^14 s^-1 = 2.650 x 10^-19 J
So, the energy of light with a frequency of 4 x 10^14 s^-1 is 2.650 x 10^-19 joules