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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The dual nature of matter and the dual nature of radiation were throughgoing concepts of physics. At the beginning of the 20th century, scientists untangled one of the best-kept secrets of nature – the wave-particle duplexity or the dual nature of matter and radiation.
Electronic Emission
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Photoelectric Effect
The photoelectric effect is a phenomenon that involves electrons getting away from the surface of materials.
Heisenberg’s Uncertainty Principle
Heisenberg’s Uncertainty Principle states that both the momentum and position of a particle cannot be determined simultaneously.