In a photocell, ultraviolet (UV) light provides enough energy to some electrons in barium metal to eject them from the surface at high speed. To measure the maximum energy of the electrons, another plate above the barium surface is kept at a negative enough potential that the emitted electrons are slowed down and stopped, and return to the barium surface. See Fig. 17-46. If the plate voltage is –3.02 V (compared to the barium) when the fastest electrons are stopped, what was the speed of these electrons when they were emitted? Plate UV light V=-3.02 V V=0 FIGURE 17–46 Barium Problem 80.

In a photocell, ultraviolet (UV) light provides enough energy to some electrons in barium metal to eject them from the surface at high speed. To measure the maximum energy of the electrons, another plate above the barium surface is kept at a negative enough potential that the emitted electrons are slowed down and stopped, and return to the barium surface. See Fig. 17-46. If the plate voltage is –3.02 V (compared to the barium) when the fastest electrons are stopped, what was the speed of these electrons when they were emitted? Plate UV light V=-3.02 V V=0 FIGURE 17–46 Barium Problem 80.

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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