An Astronomical Telescope Has an Objective Lens with Focal Length

question 15

Multiple Choice

An astronomical telescope has an objective lens with focal length f_o and has an eyepiece with focal length f_e. A second telescope has objective and eyepiece lenses with half the focal length of the first telescope. Which telescope gives the greater magnification and by what factor?

• A) The second telescope gives 4 times the magnification of the first.
• B) The first telescope gives 4 times the magnification of the second.
• C) The actual focal lengths must be known to answer this question.
• D) Both telescopes give the same magnification.

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Definitions:

Natural Monopoly

A market condition where a single firm can supply a product or service at a lower cost than any potential competitor, often due to economies of scale.

Marginal Cost

The outlay for making one more unit of a product or service.

Profit Per Unit

The amount of profit earned by selling one unit of a product or service.