If $f$ Is the Focal Length of a Convex Lens and an and an Object

question 31

Multiple Choice

If $f$ is the focal length of a convex lens and an object is placed at a distance $v$ from the lens, then its image will be at a distance $u$ from the lens, where $f , v$ , and $u$ are related by the lens equation
$$\frac { 1 } { f } = \frac { 1 } { v } + \frac { 1 } { u }$$
Find the rate of change of $v$ with respect to $u$ .

• A) \(\frac { d v } { d u } = - \frac { f } { ( u - f ) ^ { 2 } }\)
• B)
• \[\frac { d v } { d u } = - \frac { f ^ { 2 } } { u - f }\]
• C)
• \[\frac { d v } { d u } = \frac { 2 f ^ { 2 } } { ( u - f ) ^ { 2 } }\]
• D)
• \[\frac { d v } { d u } = \frac { f ^ { 2 } } { ( u - f ) ^ { 2 } }\]
• E)
• \[\frac { d v } { d u } = - \frac { f ^ { 2 } } { ( u - f ) ^ { 2 } }\]

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Definitions:

LIFO

An inventory cost methodology assuming the most recently added items to the inventory are sold first, short for "Last-In, First-Out."

FIFO

"First In, First Out," an inventory valuation method where goods first bought are the first to be sold.

Increasing Costs

Increasing Costs refer to a scenario where a company experiences a rise in the price of inputs or operational expenses over time, which can affect profitability.

Lower of Cost or Market

An accounting principle that values inventory at the lesser of its historical cost or current market value, used to ensure assets are not overstated.