If a star is twice as hot as the Sun and only half the Sun's diameter, it will be less luminous than the Sun.

Question

Quizplus · Accepted Answer

This statement is false. Luminosity depends on both temperature and size (surface area) of a star. A star that is twice as hot as the Sun will have a higher luminosity if it is also larger in size. In this case, although the star is smaller in diameter, its smaller size may not be enough to offset the effect of its higher temperature, resulting in a higher luminosity than the Sun. The actual luminosity of the star would need to be calculated based on its size and temperature using appropriate formulas.

If a Star Is Twice as Hot as the Sun