Question

What is the frequency of light that has an energy of 1.8 x 10-15 J?

Answer 1

(6.63 x 10^-34 J*s) *

Answer 2

For electromagnetic radiation,\[E = h f\]where \(h = 6.626*10^{34} \text{ J s}\) (Planck's constant)
Rearrange that to solve for \(f\) and plug in your energy...