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Oct 8, 2022 at 7:06 review Close votes
Oct 14, 2022 at 3:02
Oct 8, 2022 at 6:49 comment added Shub Does this answer your question? Why does a ray parallel to principal axis passes from focus after reflection from a concave mirror and vice a versa is also true? Why is it so?
Jul 1, 2020 at 11:54 history became hot network question
Jul 1, 2020 at 11:24 history edited Qmechanic CC BY-SA 4.0
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Jul 1, 2020 at 10:55 history edited Rajdeep Sindhu CC BY-SA 4.0
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Jul 1, 2020 at 9:00 history tweeted twitter.com/StackPhysics/status/1278252019162189824
Jul 1, 2020 at 8:01 history edited Rajdeep Sindhu CC BY-SA 4.0
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Jul 1, 2020 at 7:59 comment added Rajdeep Sindhu @FakeMod That looks interesting, although I wasn't able to understand how that works. Since I forgot to link my graph earlier, here it is - desmos.com/calculator/aijby5xlu7
Jul 1, 2020 at 7:46 comment added user258881 FWIW, I also tried out plotting such a ray diagram (a year back) in Desmos to confirm that spherical aberration exists. Here's the graph: desmos.com/calculator/jl38afrbls
Jul 1, 2020 at 5:22 comment added PM 2Ring Oops. I meant to say, the slope of the tangent through $(X,X^2)$ is $2X$. Sorry about that. But it looks like you figured out what I meant. :) Good luck!
Jul 1, 2020 at 5:20 comment added Rajdeep Sindhu You're right, I haven't learnt much calculus yet. But, fortunately, I do know the very basics of limits and derivatives. Also, I derived the power rule recently, so, I know why $\dfrac{d}{dx} x^2 = 2x$ and that would help a lot. Thanks for giving the idea!
Jul 1, 2020 at 5:17 history edited Rajdeep Sindhu CC BY-SA 4.0
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Jul 1, 2020 at 5:14 comment added PM 2Ring Ok. It's very easy to find the slope of a tangent to a parabola. I guess you haven't learned any calculus yet. The simplest parabola equation is $y=x^2$. On that parabola, the slope of the tangent through the point $(X, Y)$ has slope $2x$.
Jul 1, 2020 at 4:24 comment added PM 2Ring "Check my work" questions are off-topic here. But you have clearly put a lot of effort & perseverance into this. So I congratulate you for re-discovering spherical abberation. FWIW, try it with a parabolic reflector. It does focus properly, and the mathematics is easier.
Jul 1, 2020 at 4:19 comment added Rajdeep Sindhu @ErickShock Yeah, it took me about an hour of continuous typing to post this question. It was interesting to arrive at the result though and I learned a lot too, I made a general equation of the reflected ray when the incident ray is parallel to the principal axis. This can enable me to evaluate certain measurements with precision. Also, I made certain formulae just for this. It was fun, overall! :)
Jul 1, 2020 at 4:17 comment added PM 2Ring Please see the diagram of "Reflection from a spherical mirror" here
Jul 1, 2020 at 4:12 comment added ErickShock You really did take the long path to find out spherical aberration exists. Indeed, you did nothing wrong, it's a fact that for mirrors that span an angle bigger than (roughly) 10° of arc length parallel rays won't focus on a single point but will rather form a surface of intersecting rays. Amazingly, you can see this figure by positioning a half filled cup of coffee around a lamp
Jul 1, 2020 at 4:09 vote accept Rajdeep Sindhu
Jul 1, 2020 at 4:06 answer added Sam timeline score: 3
Jul 1, 2020 at 3:52 history asked Rajdeep Sindhu CC BY-SA 4.0