![A convex lens A of focal length 20cm and a concave lens G of focal length 5cm are kept along the same axis with the distance between them. If a parallel beam A convex lens A of focal length 20cm and a concave lens G of focal length 5cm are kept along the same axis with the distance between them. If a parallel beam](https://www.vedantu.com/question-sets/5f16a0a5-95d2-4cb5-b754-7a6788995bd93435487036600868184.png)
A convex lens A of focal length 20cm and a concave lens G of focal length 5cm are kept along the same axis with the distance between them. If a parallel beam
![Two thin convex lens L1 and L2 of focal lengths f1 and f2 respectively,are placed coaxially in contact An - Physics - Ray Optics And Optical Instruments - 10695119 | Meritnation.com Two thin convex lens L1 and L2 of focal lengths f1 and f2 respectively,are placed coaxially in contact An - Physics - Ray Optics And Optical Instruments - 10695119 | Meritnation.com](https://s3mn.mnimgs.com/img/shared/ck-files/ck_57f27e198e457.png)
Two thin convex lens L1 and L2 of focal lengths f1 and f2 respectively,are placed coaxially in contact An - Physics - Ray Optics And Optical Instruments - 10695119 | Meritnation.com
Two thin lenses of focal length f1 and f2 are in contact and coaxial. The power of the combination is .
![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
![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/sddefault.jpg)
Physics 55.4 Optics- Multiple Lenses (3 of 12) The Double Lens: The Equivalent Focal Length - YouTube
![Consider two thin lenses, one of focal length f1 and the other of focal length f2, placed in contact with each other. Apply the thin lens equation to each of these lenses Consider two thin lenses, one of focal length f1 and the other of focal length f2, placed in contact with each other. Apply the thin lens equation to each of these lenses](https://homework.study.com/cimages/multimages/16/capture5473864438025005440.png)