A Photocathode That Has a Work Function Of $2.4 \mathrm { eV }$

question 139

Multiple Choice

A photocathode that has a work function of $2.4 \mathrm { eV }$ is illuminated with monochromatic light having photon energy $3.5 \mathrm { eV }$ . What is the wavelength of this light? $\left( c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \right.$ . $\mathrm { s } , 1 \mathrm { eV } = 1.60 \times 10 ^ { - 19 } \mathrm {~J}$ )

• A) \(350 \mathrm {~nm}\)
• B) \(300 \mathrm {~nm}\)
• C) \(410 \mathrm {~nm}\)
• D) \(330 \mathrm {~nm}\)
• E) \(380 \mathrm {~nm}\)

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Definitions:

Monopolistic Competition

An economic model featuring a multitude of firms that market products which are alike but not the same, enabling a certain amount of market control and differentiation of products.

Demand Curve

A graphical representation showing the relationship between the price of a good or service and the quantity demanded by consumers.

Economic Profits

The surplus remaining after deducting both the explicit and implicit costs from a firm's total revenues.

Monopolistically Competitive Firm

A company that operates in a market with many competitors, each offering a differentiated product, allowing for some degree of price control.