You all probably dont give a damn but does anyone know of a method to log back into an instagram account?? I stupidly forgot the password. I would love any tricks you can give me!
Yes I think I'm right in what I'm saying. They can't share a common focal length. The telescope operates on the idea that it's difficult to put a distant object (a star let's say) inside the focal length length of a convex lens. So we use the objective lens to first focus an image of the object to be inside the focal length of the eyepiece, which is then magnified. Thanks for your video. This was really wrecking my head until now. Let me know if you think I'm missing anything in what I've said. Cheers.
Hi Jason I think you've got it spot on! The reason for forming the first image at the focus of the second lens is to create a virtual image at infinity: You don't have to do this, but doing so makes it easier for the eye to focus on the image, since the image is located at infinity (which is the focal point for most people's eyes). Someone with near-sighted vision, on the other hand, will have to adjust the focus differently to form the final image closer to the eye.
If the image from the first lens is formed at the focus of the second then how can you see a virtual or a real image? Isn't the light leaving the focus travelling out in parallel and so no image is formed?
according to my my textbook the ray diagram u are drawing Is for a normal adjustment telescope that means the second image will be at infinity and if an image is at infinity I thought that no object will be seen
Kosi Okoye you probably know this already by now but our eye contain a lense with focus f. Lenses have foci in either side, one outside, one inside your eyeball. When object is on infinity, then 1/f=1/infinity + 1/image distance = 0+1/image distance, so the image will appear on the same magnitude as our lense focus. We see images sharpest when images fall right on retina, so so our eye lense will change shape and make it’s focus the same distance to the retina, so in fact if object is at infinte, then all it takes to make the image clear (fall on retina) is our eye muscle and no other restriction.
Quite right. Astronomical telescopes are usually used this way as they tend to be used for extended durations. Placing the image at the near point would place significant strain on the eye. The difference in lens placement for the near point is fairly slight, anyway.
Niranjan pratap singh You're right in that for real telescopes the eyepiece generally has a smaller diameter, but that doesn't affect the way they work, just the amount of light that exits through them. The explanation given in this video is perfectly correct, regardless of diameters.
Imagine that you’re standing near a tower and pointing towards the top of it. You arm will be inclined at an upward angle. Now supposes there’s a bigger tower next to it and you point to the top of that one: Your arm will now point at a greater angle. The exact angle will depend on show tall it is. The same thing is true with telescopes: If you like a telescope up with a small object (on low magnification) the angle to the top of the object will be small. If the magnification, ion the other hand is big (making the object look bigger) the angle will be large: How large will depend on how big the object appears.
Joakim Skomsvoll because the light is approaching from an angle: The light is only focussed on centre when the light is travelling straight on towards the lens
Sorry if I'm being dense, but I was convinced that the refraction in the objective lens would solve this by bending all the light rays toward the same point (a apochromat at least would be able to do this for all wavelengths). Wouldn't the rays missing the focal point result in massive chromatic aberration?
Did not understanding anything . But just felt like I was in my grade 12 physics class and it feels good . Now no mood to grasp these principles. :( Was searching how to built a powerful telescope at home. Seeing this I think it's better to order one at Amazon. :)
why ? Visual angle with the telescope is ok ΘI, but Visual angle without telescope is Θo=(hreal/(p+fo+fe)), hreal=real height object , p=real distance of the object from the eye. MAGNIFICATION =ΘI/Θodo you confirm this mathematical formula?
This video is designed to help people understand how to draw these diagrams correctly and I can assure you that from the point of view of pre-university Physics the final diagram is 100% in line with what is expected. Could I suggest that you spend a little time studying this subject properly rather than making badly misinformed comments about something you clearly know nothing about?
You sound like Mr. Feynman. Loved the video, both content and voice.
Amazing video! I've got an exam involving these concepts tomorrow for my IB HL physics option. Thanks!
You all probably dont give a damn but does anyone know of a method to log back into an instagram account??
I stupidly forgot the password. I would love any tricks you can give me!
Thank you so much!! This is incredibly helpful. I'm going to share this with all my friends
your English is very clear
avishk kashyap m
He's British so he gotta be
In this type of telescope 2 fig. Are possible for foming virtual image .
1 if the image formed by objective lens lies b/w the fe and O
2 or on fe
thanks! this was really helpful :)
I think the image from the first lens should be inside the focus of the eyepiece lens in order to see a magnified virtual image.
That's what I think too, I was told images forming at the focal length would not be visible to viewer eye... please someone refute or verify.
Yes I think I'm right in what I'm saying. They can't share a common focal length. The telescope operates on the idea that it's difficult to put a distant object (a star let's say) inside the focal length length of a convex lens. So we use the objective lens to first focus an image of the object to be inside the focal length of the eyepiece, which is then magnified.
Thanks for your video. This was really wrecking my head until now. Let me know if you think I'm missing anything in what I've said. Cheers.
Hi Jason
I think you've got it spot on! The reason for forming the first image at the focus of the second lens is to create a virtual image at infinity: You don't have to do this, but doing so makes it easier for the eye to focus on the image, since the image is located at infinity (which is the focal point for most people's eyes). Someone with near-sighted vision, on the other hand, will have to adjust the focus differently to form the final image closer to the eye.
Why was I such a terrible student...
Things like this are super easy to understand.
Thanks!
You have help me to perform well my practice👍👍👍
If the image from the first lens is formed at the focus of the second then how can you see a virtual or a real image? Isn't the light leaving the focus travelling out in parallel and so no image is formed?
Jason Murray very nice question bro.
Jason Murray
How were you able to make those angle approximations.
It was really good video thanks for making it...you know you cleared all my concepts and doubts ...that was cool
according to my my textbook the ray diagram u are drawing Is for a normal adjustment telescope that means the second image will be at infinity and if an image is at infinity I thought that no object will be seen
Kosi Okoye you probably know this already by now but our eye contain a lense with focus f. Lenses have foci in either side, one outside, one inside your eyeball. When object is on infinity, then 1/f=1/infinity + 1/image distance = 0+1/image distance, so the image will appear on the same magnitude as our lense focus. We see images sharpest when images fall right on retina, so so our eye lense will change shape and make it’s focus the same distance to the retina, so in fact if object is at infinte, then all it takes to make the image clear (fall on retina) is our eye muscle and no other restriction.
How will the image be formed if the light rays from infinity are parallel to the principle axis?
Thanks
Video Upload coming soon:
"Miles Tails Prower Telling about Binoculars vs Telescopes"
dude can you do one video on microscope please
Very great explanation sir. Do create more videos
Tremendously helpful. Thank you
Nice video ...but do i have to use 6 cm distance or any I can take any other?? on what basis you can take the distance
Nice work!
This is normal adjustment.... What about image formation at near point?
Quite right. Astronomical telescopes are usually used this way as they tend to be used for extended durations. Placing the image at the near point would place significant strain on the eye.
The difference in lens placement for the near point is fairly slight, anyway.
Awesome tutorial!
Sir I have doubt in astronomical telescope objective lens are bigger then the eyepiece .....
Niranjan pratap singh You're right in that for real telescopes the eyepiece generally has a smaller diameter, but that doesn't affect the way they work, just the amount of light that exits through them. The explanation given in this video is perfectly correct, regardless of diameters.
Can anyone explain why the magnification is the ratio of these two angles? Does it have anything to do with Snell's law? I'm just not seeing it.
Imagine that you’re standing near a tower and pointing towards the top of it. You arm will be inclined at an upward angle. Now supposes there’s a bigger tower next to it and you point to the top of that one: Your arm will now point at a greater angle. The exact angle will depend on show tall it is.
The same thing is true with telescopes: If you like a telescope up with a small object (on low magnification) the angle to the top of the object will be small. If the magnification, ion the other hand is big (making the object look bigger) the angle will be large: How large will depend on how big the object appears.
So relaxing to watch the drawing
Why are the light rays curved
man i am not able to find ur nxt video??
Thank you so much!!!
You video is very interesting. But very people no understand English 🙏
nyc video thanks for making it
Why is the focal point drawn off centre?
Joakim Skomsvoll because the light is approaching from an angle: The light is only focussed on centre when the light is travelling straight on towards the lens
Sorry if I'm being dense, but I was convinced that the refraction in the objective lens would solve this by bending all the light rays toward the same point (a apochromat at least would be able to do this for all wavelengths). Wouldn't the rays missing the focal point result in massive chromatic aberration?
Did not understanding anything . But just felt like I was in my grade 12 physics class and it feels good . Now no mood to grasp these principles. :(
Was searching how to built a powerful telescope at home. Seeing this I think it's better to order one at Amazon. :)
why ? Visual angle with the telescope is ok ΘI, but Visual angle without telescope is Θo=(hreal/(p+fo+fe)), hreal=real height object , p=real distance of the object from the eye. MAGNIFICATION =ΘI/Θodo you confirm this mathematical formula?
thks sir
1:00 the incoming light rays that fall on objective lens should be e parallel to the axis and not at an angle like you have drawn.
nice video sir
I can use any distance between the 2 lenses?
Drennix Guerrero yeh
Why are they not straight
Please answer me
The light rays ARE straight - that’s why I drew them with a ruler. The only times they are not straight is as they enter or leave the lenses.
Hello you can add subtitles in spanish???
Nice
Thanks
Thank you very much
at last why its not fe upon fo
thank u
Thanks
Can we reach to the infinity
😁😇😁😁
thank you to share.
Good
very nice explanation!
Extra THICC .
Bro your lenses are wrong
Objective lenses should be smaller and eye piece should be bigger.....
#astronomicaltelescopes
Its wrong because the principle exis doesn't pass to optical center
Edgu
geeeddeeeeee
Objective lens is bigger than eyepiece
That's the huge mistakee
That's how it should be.
This diagram is 100% wrong ! avoid this kind of thing on the web
This video is designed to help people understand how to draw these diagrams correctly and I can assure you that from the point of view of pre-university Physics the final diagram is 100% in line with what is expected.
Could I suggest that you spend a little time studying this subject properly rather than making badly misinformed comments about something you clearly know nothing about?