Concept explainers
The value of the Planck’s constant and the work function of the metal.
Answer to Problem 39P
The value of the Planck’s constant is
Explanation of Solution
Write the expression for the kinetic energy of the electron.
Here,
Write the expression for the energy of the photon of particular wavelength.
Here,
Write the expression for the work function of the metal.
Here,
Conclusion:
Substitute
Substitute
Substitute
Substitute
Substitute
Substitute
Subtract the equation (IV) from (V).
Thus, the value of the Planck’s constant is
Substitute
Thus, the value of the Planck’s constant is
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Chapter 3 Solutions
Modern Physics for Scientists and Engineers
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