3-44. When light of wavelength 450 nm is incident on potassium, photoelectrons with stopping potential of 0.52 V are emitted. If the wavelength of the incident light is changed to 300 nm, the stopping potential is 1.90 V. Using only these numbers together with the values of the speed of light and the electron charge, (a) find the work function of potas- sium and (b) compute a value for Planck's constant.

3-44. When light of wavelength 450 nm is incident on potassium, photoelectrons with stopping potential of 0.52 V are emitted. If the wavelength of the incident light is changed to 300 nm, the stopping potential is 1.90 V. Using only these numbers together with the values of the speed of light and the electron charge, (a) find the work function of potas- sium and (b) compute a value for Planck's constant.

University Physics Volume 3

17th Edition

ISBN:9781938168185

Author:William Moebs, Jeff Sanny

Publisher:William Moebs, Jeff Sanny

Chapter6: Photons And Matter Waves

Section: Chapter Questions

Problem 6.7CYU: Check Your Understanding Cut-off frequency for the photoelectric effect in some materials is 8.01013...

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