Sodium has a work function of 2 eV. Calculate the maximum energy and speed of the emitted electrons, when sodium is illuminated by radiation of wavelength 150 nm:
Correct Answer :
Solution :
The correct option is:
Step-by-Step Explanation:
1. Identify the Given Parameters:
Work function of sodium,
Wavelength of incident radiation,
Planck's constant,
Speed of light,
Mass of an electron,
2. Convert the Work Function to Joules:
Since 1 eV =
:
3. Calculate the Incident Photon Energy (E):
Using the photon energy formula:
Substituting the values:
This corresponds to the incident energy value shown in the option:
.
4. Calculate the Maximum Kinetic Energy (Kmax) of Emitted Electrons:
Using Einstein's photoelectric equation:
5. Calculate the Maximum Speed (vmax):
The relation between kinetic energy and speed is:
Solving for speed:
Substitute the values into the equation:
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