Concept explainers
Magnitude of Stars The magnitude M of a star is a measure of how bright a star appears to the human eye. It is defined by
where B is the actual brightness of the star and
(a) Expand the right-hand side of the equation.
(b) Use part (a) to show that the bright a star, the less its magnitude.
(c) Betelgeuse is about 100 times brighter than Albiero. Use part (a) to show that Betelgeuse is 5 magnitudes less bright than Albiero.
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Chapter 4 Solutions
ALGEBRA AND TRIGONOMETRY-WEBASSIGN
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