While most transition metals have work functions corresponding to photon frequencies that are larger (higher) than visible light, alkali and alkaline earth metals have low-energy work functions. For example, calcium has a work function of Po = 4.3419×10-19 J. (a) What is the initial state n; for the hydrogen emission lines at visible wavelengths (i.e., those with ng = 2) for the lowest-energy photon that would eject an electron from calcium? (b) If the colors of the visible hydrogen emission lines (n; = 3 to n; = 6) are red, green, blue and violet, which colors are capable of ejecting the electrons from calcium? (c) The energy of the emitted photon you identified in part (a), is not identical to the workfunction of calcium. Therefore, the electron is ejected from the metal surface with some kinetic energy (i.e., energy is conserved in the photoelectric effect process). What would the velocity of the electron ejected from calcium (in meters per second)?

While most transition metals have work functions corresponding to photon frequencies that are larger (higher) than visible light, alkali and alkaline earth metals have low-energy work functions. For example, calcium has a work function of Po = 4.3419×10-19 J. (a) What is the initial state n; for the hydrogen emission lines at visible wavelengths (i.e., those with ng = 2) for the lowest-energy photon that would eject an electron from calcium? (b) If the colors of the visible hydrogen emission lines (n; = 3 to n; = 6) are red, green, blue and violet, which colors are capable of ejecting the electrons from calcium? (c) The energy of the emitted photon you identified in part (a), is not identical to the workfunction of calcium. Therefore, the electron is ejected from the metal surface with some kinetic energy (i.e., energy is conserved in the photoelectric effect process). What would the velocity of the electron ejected from calcium (in meters per second)?

University Physics Volume 3

17th Edition

ISBN:9781938168185

Author:William Moebs, Jeff Sanny

Publisher:William Moebs, Jeff Sanny

Chapter8: Atomic Structure

Section: Chapter Questions

Problem 101AP: A student in a physics laboratory observes a hydrogen spectrum with a diffraction grating for the...

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