## Blinding (Sun)Light

Looking directly at the noonday sun on a clear day can blind you. What is the intensity of that blinding sunlight reaching your eyes in W/m^2? The sun has a luminosity of about 4 x 10^26 W and is 1.5 x 10^11 meters from us.

Hint
Intensity:
$$I=\frac{L}{4\pi R^2}$$$where $$L$$ is the luminosity, and $$R$$ is the distance. Hint 2 Don’t worry about converting any units. Intensity: $$I=\frac{L}{4\pi R^2}$$$
where $$L$$ is the luminosity, and $$R$$ is the distance. Thus,
$$I=\frac{4\cdot 10^{26}W}{4\pi (1.5\cdot 10^{11}m)^2}=\frac{10^{26}W}{2.25\pi \cdot 10^{22}m^2}$$$$$=\frac{10^{4}}{2.25\pi }W/m^2=1415\:\frac{W}{m^2}$$$
$$1415\: W/m^2$$\$