![a) Determine the 'effective focal length' of the combination of the two lenses in Exercise 9.10, if they are placed 8.0 cm apart with their principal axes coincident. Does the answer depend a) Determine the 'effective focal length' of the combination of the two lenses in Exercise 9.10, if they are placed 8.0 cm apart with their principal axes coincident. Does the answer depend](https://d10lpgp6xz60nq.cloudfront.net/physics_images/U_LIK_SP_PHY_XII_C09_E01_021_S01.png)
a) Determine the 'effective focal length' of the combination of the two lenses in Exercise 9.10, if they are placed 8.0 cm apart with their principal axes coincident. Does the answer depend
![Physics 55.4 Optics- Multiple Lenses (3 of 12) The Double Lens: The Equivalent Focal Length - YouTube Physics 55.4 Optics- Multiple Lenses (3 of 12) The Double Lens: The Equivalent Focal Length - YouTube](https://i.ytimg.com/vi/GxemspUuOSU/hqdefault.jpg)
Physics 55.4 Optics- Multiple Lenses (3 of 12) The Double Lens: The Equivalent Focal Length - YouTube
![When two thin lenses are kept in contact prove that their combined or effective focal length F is given by 1F1F11F2 where the terms have their usual meaning When two thin lenses are kept in contact prove that their combined or effective focal length F is given by 1F1F11F2 where the terms have their usual meaning](https://content-grail-production.s3.amazonaws.com/quetsion-media/24066af9-5039-4636-b492-415c8f1e7ec2-image.png)
When two thin lenses are kept in contact prove that their combined or effective focal length F is given by 1F1F11F2 where the terms have their usual meaning
![Derivation of Equivalent Focal Length of Combination of two lens separated by distance #kamaldheerya - YouTube Derivation of Equivalent Focal Length of Combination of two lens separated by distance #kamaldheerya - YouTube](https://i.ytimg.com/vi/JTOSQLL93pY/maxresdefault.jpg)
Derivation of Equivalent Focal Length of Combination of two lens separated by distance #kamaldheerya - YouTube
![Focal length, focal distance, dioptric power, curved mirror, lens equation, microscope, photographic objective, focus, beam radius Focal length, focal distance, dioptric power, curved mirror, lens equation, microscope, photographic objective, focus, beam radius](https://www.rp-photonics.com/img/focal_length.png)
Focal length, focal distance, dioptric power, curved mirror, lens equation, microscope, photographic objective, focus, beam radius
![Physics 55.4 Optics- Multiple Lenses (3 of 12) The Double Lens: The Equivalent Focal Length - YouTube Physics 55.4 Optics- Multiple Lenses (3 of 12) The Double Lens: The Equivalent Focal Length - YouTube](https://i.ytimg.com/vi/GxemspUuOSU/mqdefault.jpg)
Physics 55.4 Optics- Multiple Lenses (3 of 12) The Double Lens: The Equivalent Focal Length - YouTube
When two thin lenses are kept in contact, prove that their combined or effective focal length F is given by 1/F = 1/f1 + 1/f2 where the terms have their usual meaning.
Derive the expression for effective focal length of two thin lenses kept in contact. - Sarthaks eConnect | Largest Online Education Community
![optics - How is focal length defined for a two-lens system, separated by a distance $d$? - Physics Stack Exchange optics - How is focal length defined for a two-lens system, separated by a distance $d$? - Physics Stack Exchange](https://i.stack.imgur.com/fwrwB.png)