Huygen's wave theory of light could not explain

By Huygens's wave theory of light we cannot explain the phenomenon of

In case of photoelectric effect experiment explain the following facts giving reasons: The wave theory of light could not explain the existence of the threshold frequency.

Wave theory of light only can explain

By Huygen's wave theroy of light, we cannot explain the phenomenon of

By Huygen's wave theroy of light, we cannot explain the phenomenon of

The wave theory of light does not explain