Radiations of frequency `10^(15)Hz` is incident on three photosenstive surfaces. A,B and C. Following observations are recorded,
(a) Surface A. No photoemission occurs.
(b) Surface B. Photoemission occurs but the photoelectrons have zero kinetic energy.
(c) Surface C. Photoemission occurs and photoelectrons have some KE.
Based on Einstein's photoelectric equation, expalain the three observations.

Explanation

To explain the observations based on Einstein's photoelectric equation, we can analyze each surface (A, B, and C) step by step.

### Step-by-Step Solution:

1. **Understanding Einstein's Photoelectric Equation**:
The photoelectric effect can be described by Einstein's equation:
\[
KE_{max} = h\nu - \phi
...