For those who are having trouble with optics (mirror/lens) on PS section

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kehlsh

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This is a fairly intuitive guide for optics.
I believe this can help a lot of people.

http://www.mediafire.com/?bn81pmnxv8jzbm6


PS
Errors
#3 should be i = -20m and m = 5 and thus be Upright and Virtual.
#6. virtual upright, not virtual inverted
sorry about these XD
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kehlsh said:
I got bored after filling out AMCAS and finishing up 6/16 MCAT.
So I made this little guide for optics. I hope some of the stuff you will get benefit from.

Do forgive any mistakes I might have made, whether in terms of content or grammar. I mean no offense =X.

http://www.mediafire.com/?bn81pmnxv8jzbm6

If there is positive I am willing to create more of such guides. Thanks~
Click to expand...

Stellar :):thumbup:
 
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I think this is awesome!

I've always wanted to write a textbook, or a review book. Biology is my forte. I love that stuff. Maybe we should get together and make our own version of TBR... but BETTER.
 
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I have never gotten optics, although maybe it's because EK was far too brief in explaining it. I will look at this next week! Thank you for your generosity in sharing!
 
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Dude I'm not even there yet but this makes me look forward to physics (or as much forward as I possibly can because it's my worst subject haha) in a couple of days. Thank you.
 
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Kehlsh is a genius. Just sayin'.

If you want more of his geniusness, you should join the Skype group and talk to him. :)
 
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This is awesome! You've really put a lot of time and effort into it, and it's great! Thank you :)
 
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due to the positive feedback, I think i'll make another one on simple harmonic motion ( i like these)
 
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kehlsh said:
I got bored after filling out AMCAS and finishing up 6/16 MCAT.
So I made this little guide for optics. I hope some of the stuff you will get benefit from.

Do forgive any mistakes I might have made, whether in terms of content or grammar. I mean no offense =X.

http://www.mediafire.com/?bn81pmnxv8jzbm6

If there is positive I am willing to create more of such guides. Thanks~
Click to expand...

Hey Kehlsh thanks a lot for the guide. I was doing #3 and shouldn't

i = -20m and m = 5 and would thus be Upright and Virtual?
 
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yea sorry about those mistakes I made them up really fast while I was sitting at the dinner XD i'll post the fix in the OP
 
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bump in case ppl need it

I know I'm looking back at this as I retake... *sad life*
 
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kehlsh said:
bump in case ppl need it

I know I'm looking back at this as I retake... *sad life*
Click to expand...

Dude, you rock. Can you make one on simple harmonic motion as you said? This is my weakest science topic ever because I never took it before (my professor in college never bothered to cover it). Thanks a bunch!
 
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dannydickman said:
Bump for great justice! (and so I can find it later).

Say, did you ever end up doing the simple harmonic motion bit?
Click to expand...

I was doing it but then I realized it's very hard so I sorta gave up.

If you wanna discuss any MCAT topics I'm usually on whenever I'm on computer @ skype (ID - xispec)

feel free to add if u wanna discuss... 'n don't forget to do verbal passage each day !
 
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I don't know if this will help or not but it did for me. I don't like memorizing since it's easy to make recall mistakes. What I do when deciding positives and negatives: I look at where light wants to go. For instance, a mirror reflects light so light would want to be on the reflected side and that side is positive. Whereas a lens lets light to pass through, thus, the positive for lenses is on the other side of the object/observer.
 
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BTW, your guide is AWESOME! Why can't profs teach like this? I'm an engineer and even after all the engineering physics I took, I didn't get optics until I started reviewing for MCAT. Had to figure things out on my own but your guide is nonetheless a great summary, esp. for quick reviews. Truly a piece of work! I wish I had it earlier--would have saved me a lot of time! I await your SHM! haha...hopefully before my Aug 6th exam. It would solidify these concepts for me. Ever thought about writing a textbook? I would buy it even if the prof doesn't require it! :p
 
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jellybeano said:
Oh, if you have time, an E/M guide would also be greatly appreciated!!!
Click to expand...

I would do it if I didn't spend so much time on improving Verb a Derb.

Maybe while I review E/M I might consider doing it just for the fun.! (since response is good)
 
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in problem 8

when you have

1/60 = 1/50 + 1/x

what's the algebra behind that.. to give you x = -300?
do you try to convert it to decimals? or is there an easier way?

thanks
 
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thanks a bunch my friend. I absolutely hated optics. thanks to you, mirrors and lenses make sense to me. I was always looking for simple rules to follow and you have done just that. Thanks again and i hope this helps me gain a few points on my exam! :xf:
 
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I just remember for diverging lenses/mirrors, everything is smaller, upright, virtual and within the focal length.

For converging mirrors/lenses, know that as you move the object further away, the image gets closer to the focal point and smaller. As you move it closer, the opposite happens. TBR has a good summary of it:

If object beyond R, image forms between R and f.

If object at R, image will form at R.

If object between R and f, image will form beyond R.

If object at f, no image.

If object within f, image is larger, upright, virtual.

this formula is also cool: i = (o x f) / (o - f)

edit: sorry, do not mean to steal your thunder kehlsh. this is just the strategy I use. It's easier for me to visualize and POE than to calculate the answer.
 
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muhali3 said:
I just remember for diverging lenses/mirrors, everything is smaller, upright, virtual and within the focal length.

For converging mirrors/lenses, know that as you move the object further away, the image gets closer to the focal point and smaller. As you move it closer, the opposite happens. TBR has a good summary of it:

If object beyond R, image forms between R and f.

If object at R, image will form at R.

If object between R and f, image will form beyond R.

If object at f, no image.

If object within f, image is larger, upright, virtual.

this formula is also cool: i = (o x f) / (o - f)

edit: sorry, do not mean to steal your thunder kehlsh. this is just the strategy I use. It's easier for me to visualize and POE than to calculate the answer.
Click to expand...


thank you. you are the MAN! i am just going to memorize this as best as possible lol
 
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muhali3 said:
I just remember for diverging lenses/mirrors, everything is smaller, upright, virtual and within the focal length.

For converging mirrors/lenses, know that as you move the object further away, the image gets closer to the focal point and smaller. As you move it closer, the opposite happens. TBR has a good summary of it:

If object beyond R, image forms between R and f.

If object at R, image will form at R.

If object between R and f, image will form beyond R.

If object at f, no image.

If object within f, image is larger, upright, virtual.

this formula is also cool: i = (o x f) / (o - f)

edit: sorry, do not mean to steal your thunder kehlsh. this is just the strategy I use. It's easier for me to visualize and POE than to calculate the answer.
Click to expand...

I LOVE their method. :love: :love: :love:

It is absolute genius and seriously makes everything so fast and easy. It's all of the little tricks like this that make waiting for the books to arrive so worth it.

The poster who asked about f = 60 and object = 50 and then did all the long math proved my love for their trick once again.

(50 x 60)/(50 - 60) = (50 x 60)/(-10) = - (5 x 60) = -300. Can be done in your head. You can also use their visualization suggestion of object being inside of f on a converging mirror.
 
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This saved me another question in GS 6!

I highly suggest you understand the intuition behind this method!
 
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