(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Hi everyone,

I was wondering if anyone can help me out with my project in physics. Our goal is to make the sun image appear on a panel at the end of a rail, using lens, to see if we can observe sunspots on the projected image of the sun.

This is the materials we have :

-rail of 120 cm

-a panel of 20x16 cm (so the diameter of the image of the sun would best be around 10cm if possible)

- Lens of different focal distance : +50 mm, +100 mm, +200mm, +250mm, and one -150mm

___________

2. Relevant equations

Theres the equation I got but these are from french class so might be different I am not sure.

1/p + 1/q = 1/f

m = -q/p

Sun distance : 1.5 x 10^11 m

Sun diameter 1.392 x 10^9 m

3. The attempt at a solution

From what I understand, the setup should look like this on the rail :

LENS1_____________LENS2_____________________PANEL

I believe I should place a positive focal distance lens first right? like the +250mm, and then the -150mm... but Im having a bit of trouble calculating the distance between the lens and the panel on the rail to get a clear image of the sun at the good diameter. When I calculate that I want a 10cm image of the sun, I get that I need a 10 m LENS and that my image would also be at 10m... its too far for my setup!

Thanks a lot in advance

- Seifer

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# Homework Help: Observing the image of the sun (optic)

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