Question
The surface temperature of Arcturus is about half as hot as the Sun's, but Arcturus is about 100 times more luminous than the Sun. What is its radius, compared to the Sun's?
Step 1
We know that the luminosity of a star is proportional to its surface area and the fourth power of its temperature. Mathematically, this can be represented as: L = k * A * T^4 where L is the luminosity, k is a constant, A is the surface area, and T is the Show more…
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