Use the Following Figure for the Next Two Questions $\times$ 10^-19 J

question 8

Multiple Choice

Use the following figure for the next two questions.
Apparatus for studying the photoelectric effect
-The work function of the material being investigated is 3.8 $\times$ 10^-19 J.Light of a wavelength 350 nm is incident on the material.What is the lowest voltage needed between the cathode (C) and the anode (A) to stop any electrons ejected from the cathode from reaching the anode?

• A)2.37 V
• B)1.17 V
• C)3.54 V
• D)4.71 V
• E)None of these is correct.

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Definitions:

Hydrogen

Hydrogen is a chemical element with the symbol H and atomic number 1, known as the lightest element in the periodic table and a primary component of water.

Water

A transparent, tasteless, odorless, and nearly colorless chemical substance that is the main constituent of Earth's streams, lakes, and oceans.

Potassium

A soft, silvery-white metallic element, very reactive, especially in water, and essential for plant and animal life.

KCl

KCl, known as potassium chloride, is a metal halide salt composed of potassium and chlorine, used in medicine, food processing, and as a fertilizer.