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College Physics
11th Edition
ISBN: 9781305952300
Author: Raymond A. Serway, Chris Vuille
Publisher: Cengage Learning
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Consider a bright star in our night sky. Assume its distance from Earth is 29.0 light-years (ly) and its power output is 4.00 x 104° w, about 100 times that of the Sun. One light-year is the distance traveled by light through a vacuum in one year.
(a) Find the intensity of the starlight at the Earth.
W/m?
(b) Find the power of the starlight the Earth intercepts. (The radius of Earth is 6.38 × 10° m.)
MW
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Consider a bright star in our night sky. Assume its distance from Earth is 29.0 light-years (ly) and its power output is 4.00 x 104° w, about 100 times that of the Sun. One light-year is the distance traveled by light through a vacuum in one year.
(a) Find the intensity of the starlight at the Earth.
W/m?
(b) Find the power of the starlight the Earth intercepts. (The radius of Earth is 6.38 × 10° m.)
MW
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