A window of a submarine is 30 cm thick, and is underwater. The index of refraction of the window is 1.65. The index of refraction fo th eocean is 1.35. The index of refraction inside the submarine is 1.00. A scuba diver is 1 meter away from thw window. Where does his image form? I used n1/d_o + n2/d_i = (n2-n1)/R (this goes to zero since R is infinity), from the Thick Lens Equation. 1.35/100 = -1.65/d_i d_i = -122.22 Now d_o2 = 152.22, because of the thickness thing (d_i+d_o2 = thickness) Again; n/d_o2 + n/d_i2 = (some n - some n)/infinity (goes to zero again) Which n values do I use? Is it 1.65/152.222 + 1/d_i2 =0 or is it 1.65/152.222+1.35/d_i2 =0 ??