KCET · Physics · Dual Nature of Matter
Light of energy \(E\) falls normally on a metal of work function \(\frac{E}{3}\). The kinetic energies \(K\) of the photo electrons are
- A \(K=\frac{2 E}{3}\)
- B \(K=\frac{E}{3}\)
- C \(0 \leq K \leq \frac{2 E}{3}\)
- D \(0 \leq K \leq \frac{E}{3}\)
Answer & Solution
Correct Answer
(C) \(0 \leq K \leq \frac{2 E}{3}\)
Step-by-step Solution
Detailed explanation
Given, work function, \(\phi_0=E / 3\)
According to Einstein's photoelectric equation,
\(K_{\max }=E-\phi_0=E-\frac{E}{3}\)
\(\Rightarrow \quad K_{\max }=\frac{2 E}{3}\)
\(\therefore\) Kinetic energy lies between 0 to \(2 E / 3\).
According to Einstein's photoelectric equation,
\(K_{\max }=E-\phi_0=E-\frac{E}{3}\)
\(\Rightarrow \quad K_{\max }=\frac{2 E}{3}\)
\(\therefore\) Kinetic energy lies between 0 to \(2 E / 3\).
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