Can you please help me with these questions and add some comments to the summary
ID: 3278343 • Letter: C
Question
Can you please help me with these questions and add some comments to the summary and conclusion if possible. The data from the converging and diverging lens experiment is attached along with extra information about the experiment.
See Data on Wekt Paqe To Answer these Quesions secriment &Focal; Leath of lens Anabris 1. Refer to focal lengths obtained by procedures 2 and 3 Are the f-valoes the same for a given lens? If not, what is the deviation? What cou the cause of the deviation? 2. Refer to the focal lengths estimated by procedure 4 (using the optic bench). How does the focal length compare with values estimated in procedures 2 and 3? 3. (a) You have a concave lens whose focal length has an absolute value of 10 em and several coevex lenses with f 5 cm, 8 cm, 12 cm. 15 em, and 20 em. Which of the convex lenses can be used to determine the focal length of the concave lens? Give your reason. Summary and Conclusions 50Explanation / Answer
1. The f-values are indeed, not the same. The deviation of the f values are fm-fDO,
where these two represents focal length determination by magnification and a distant object. This deviation happens because parallel rays coming from a further light bulb converge accurately at the focal point, but the eye remains much nearer than that bulb, so the parallel ray approximation introduces some errors in the reading- making the later less accurate.
2. The optical bench reading resembles procedure 3 (parallel rays from bulb) than the reading by magnification method.
3. As the diopter power indicates the converging power of a lens, so to make a lens system which will determine the focal length of the concave lens, we have to make it converging. And this is possible only when the concave lens will have less power or more focal length than the convex converging lenses.
So, f=5 and 8 cm lenses will only be suitable to determine the focal length of the cocave lens.
Summery & conclusion:
Parallel rays parallel to the optical axis of a converging system will always converge at the focal point of the system. Any deviation from the above condition will induce error to the final data. lenses with combined and different magnification power will yield a converging system only if the convex lens has lesser focal length than the diverging concave lens.