By What Factor Is the Light-Gathering Power of the 10-M-Diameter

question 337

Multiple Choice

By what factor is the light-gathering power of the 10-m-diameter Keck telescope on Mauna Kea in Hawaii greater than an average unaided human eye,with a typical aperture diameter of 5 mm?

• A) 2.5 × 10⁵ times
• B) 2 × 10⁴ times
• C) 2000 times
• D) 4 × 10⁶ times

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Definitions:

Internal Consistency

The degree of reliability within a test—the extent to which different parts of the same test yield the same results.

Split-Half Reliability

A measure of internal consistency, often ascertained by comparing responses on odd-numbered test items with responses on even-numbered test items and seeing if the scores for these responses are correlated.

Coefficient Alpha

A method for evaluating internal consistency, calculated by averaging the intercorrelations of all the items on a given test. The higher the coefficient alpha, the higher the internal consistency.