Our Sun has a peak emission wavelength of about 500 nm and a radius of about 700,000 km. Your dark-adapted eye has a pupil diameter of about 7 mm and can detect light intensity down to about 1.5 x 10-11 W/m2. Assume the emissivity of the Sun is equal to 1.
Our Sun has a peak emission wavelength of about 500 nm and a radius of about 700,000 km. Your dark-adapted eye has a pupil diameter of about 7 mm and can detect light intensity down to about 1.5 x 10-11 W/m2. Assume the emissivity of the Sun is equal to 1.
First, given these numbers, what is the surface temperature of the Sun in Kelvin to 3 significant digits?
What is the power output of the Sun in moles of watts? (in other words, take the number of watts and divide it by
Assuming that all of the Sun's power is given off as 500 nm photons*, how many photons are given off by the Sun every second? Report your answer to the nearest power of 10 (e.g. if you got 7 x 1024, give your answer as 25).
Given these values and the properties of the eye, from how far away can you see (detect) the Sun? Give your answer in units of 'parsecs' (https://en.wikipedia.org/wiki/Parsec) to 2 significant digits. A parsec is, roughly, the distance between our Sun and the closest star, Alpha Centauri.
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