When photon of energy 3.8 eV falls on metallic suface of work function 2.8 eV , then the kinetic energy of emitted electrons are

Options

A. 1 eV
B. 6.6 eV
C. 0 to 1 eV
D. 2.8 eV

Answer

To solve the problem of finding the kinetic energy of emitted electrons when a photon of energy 3.8 eV falls on a metallic surface with a work function of 2.8 eV, we can use Einstein's photoelectric equation. Here’s the step-by-step solution:

### Step 1: Understand the Given Values
- Energy of the incident photon (E) = 3.8 eV
- Work function of the metal (W₀) = 2.8 eV

### Step 2: Use Einstein's Photoelectric Equation
Einstein's photoelectric equation states:
\[ E = W₀ + KE_{max} \]
where:
- \( E \) is the energy of the incident photon,
- \( W₀ \) is the work function of the metal,
- \( KE_{max} \) is the maximum kinetic energy of the emitted electrons.

### Step 3: Rearrange the Equation to Solve for Kinetic Energy
We can rearrange the equation to find the maximum kinetic energy:
\[ KE_{max} = E - W₀ \]

### Step 4: Substitute the Values
Now, substitute the given values into the equation:
\[ KE_{max} = 3.8 \, \text{eV} - 2.8 \, \text{eV} \]

### Step 5: Perform the Calculation
Calculate the kinetic energy:
\[ KE_{max} = 1.0 \, \text{eV} \]

### Step 6: Conclusion
The maximum kinetic energy of the emitted electrons is 1.0 eV. Therefore, the kinetic energy of the emitted electrons will range from 0 to 1.0 eV.

### Final Answer
The kinetic energy of the emitted electrons is **1 eV**.

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