A Photocathode Whose Work Function Is 2

question 67

Multiple Choice

A photocathode whose work function is 2.9 eV is illuminated with white light that has a continuous wavelength band from 400 nm to 700 nm.What is the range of the wavelength band in this white light illumination for which photoelectrons are not produced? (c = 3.00 × 10⁸ m/s,h = 6.626 × 10^-34 J ∙ s,1 eV = 1.60 × 10^-19 J)

• A)430 nm to 700 nm
• B)400 nm to 480 nm
• C)430 nm to 480 nm
• D)400 nm to 430 nm
• E)480 nm to 700 nm

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Definitions:

Break-Even Sales

The amount of revenue required to cover both the variable and fixed costs of a business, resulting in neither profit nor loss.

Margin Of Safety

The difference between actual sales and sales at the break-even point, providing a cushion that measures the business's ability to withstand sales fluctuations.

Current Sales

The total revenue generated from goods or services sold by a company during the current period.

Break-Even Sales

The amount of revenue required to cover both the fixed and variable costs of a business, indicating the point at which profit starts to be generated.