The work function for two metals are 9eV and 4.5eV. Find the approx. difference between their threshold wavelength. (use hc = 1240 eV - nm)
- 138 nm
- 130 nm
- 112 nm
- 145 nm
The Correct Option is A
Solution and Explanation
The correct option is (A): 138 nm
\(\Delta \lambda=[\frac{1240}{4.5}-\frac{1240}{9}]\)nm
= 138 nm
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Concepts Used:
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Heisenberg’s Uncertainty Principle states that both the momentum and position of a particle cannot be determined simultaneously.