GCSE Physics - How Lenses Work #69

This video covers
- The difference between convex and concave lenses
- What 'principal focus' and 'focal length' are
- The difference between real and virtual images
Exam board specific info:
AQA - Separate science only
IGCSE Edexcel - Not in your course
Edexcel - Separate science only
OCR 21st Century - Separate science only
OCR Gateway - Separate science only
Maths Playlist:
• GCSE Maths (9-1)
GCSE Chemistry playlist:
• GCSE Chemistry - Atoms...
GCSE Biology Playlist:
• Video
GCSE Physics Playlist:
• Video

[@mytutorsammy1624]

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[@Cognitoedu]

Thankyou so much Sammy, we really appreciate messages like this 🤩. Great to hear that your students have been finding them so useful and that we could help them continue their education even during the pandemic. All the best 😊

[@Cognitoedu]

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That’s great to hear - thanks for taking the time to leave us a comment 🥳

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[@kobiecamp1134]

COGNITO, thank you for your services of supplying us with good details on how the lenses function. You are truly a excellent teacher of optical technology. But here's a question I have: how does the lenses in a camera correct the inverted image(from a convex lens) into a upright position? Is it done by combining a convex lens with a concave lens because a concave lens give off an upright image, or is there something else at play?

[@elenabarcan6355]

In a camera, the inverted image created by the convex lens (the primary lens) is indeed corrected, but not by directly re-inverting the image to make it appear upright to the naked eye. Instead, the correction process differs based on the type of camera and the technology it uses. In digital cameras for example, the convex lens in a digital camera projects an inverted image onto the image sensor (such as a CCD or CMOS sensor). The sensor captures the image as it is projected (inverted), and then digital image processing software within the camera automatically corrects the image. The software flips the image right-side-up before displaying it on the camera’s screen or storing it on memory.

[@Astronomynatureandmusic]

Great video. Question: the chicken image on the screen at 4:28 appears to be behind the focal point. Is that correct?

[@excaliber2845]

the chicken is on the focal point not behind it

[@varunmotwani4129]

Thanks man

[@mohmadzahriny9667]

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[@user-wi2hi3lv6o]

How do you animate these videos

[@rafii-baloch9341]

Awesome 👌🏻

[@zni1925]

The video is fantastic, but the correct spelling is principal focus and not principle focus

[@Cognitoedu]

Cheers for pointing that out!

[@jaigoyal2794]

Also - i don't think real images are smaller - surely they're same size? If not, please explain

[@jaigoyal2794]

@cognito

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[@kakashismyfav]

thankyou ml

[@nxgyt7461]

What about short sighted and long sighted

[@lukecollins4130]

Good video thanks

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i disagree

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Nice.

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Perfetto

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1:27 1:28 1:28 1:29

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[@iainhenderson4222]

BTW. It's principAL focus.

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3:28

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2:43

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me

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Really helpful video but I still got a 2 out of 8 in my test.

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[@Great_sri_lankan]

Hi guys.. anyone from royal institute?

[@DanielMay-zk6ib]

Lenses piss me off

[@billy8012]

#69

[@RandomGuy-yy3ng]

Who's in Mr Ngirandi's class

[@user-ub2nw4pr2i]

Someone in Tr Tonny’s and Alex’s class???

[@Zen__17]

Nah

[@ahmetbasaranX]

0:37 observing the light path in the lens inspired me to do that: kzbin.info/www/bejne/a6mZqnR3qM6ImaM

[@christels9675]

a

[@muizHD]

BRO I CANT UNDERSTAND THIS WTH IS A FOCAL POINT

[@ElectrossHD]

the point at x from the lense

[@alexstone1074]

Who in Kroon's Class!!!!!

[@suchirgpta]

Me

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Hitler

[@aishie2000]

Who's kroon?

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@@aishie2000 probably their school teacher

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I am Kroon

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Marling physics gang

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2023

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i came here because of the number in the title

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?

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James ew

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#69

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#69