**1. The problem statement, all variables and given/known data**

What will be the irradiance (power per unit area) in the image, if the Sun’s irradiance at the sea level is I = 500W/m^2

Lens is 200mm f

Sun is 150×10^9 m away

Diameter of sun is 1.4×10^9 m

**2. Relevant equations**

**3. The attempt at a solution**

I know that at the lens the irradiance will be the same i.e. 500W/m^2 but at the image the irradiance will be magnified. I’m not sure how to get there though.

I know an image of the sun will be .2m from the lens and the diameter of the image will be .00187m because M=di/do = .2m/150×10^9 = 1.333X10^-12 and 1.333×10^-12 multiplied by the diameter of the sun is .000187m.

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