- #1
Dhananjay97
- 3
- 0
Member warned about proper use of the template and showing an attempt at solution.
Image distance after passing through lens and mirror
Click For Summary
Homework Help Overview
The discussion revolves around a problem involving a lens and a mirror, where participants are trying to determine the final image distance after light passes through the lens and reflects off the mirror. The focal lengths of the lens and mirror, as well as the distances involved, are provided, but the original poster expresses confusion about their calculations.
Discussion Character
- Exploratory, Assumption checking, Problem interpretation
Approaches and Questions Raised
- The original poster attempts to apply the lens formula but encounters difficulties with the results. They describe their calculations for both the lens and the mirror, noting different approaches to find the image distance. Some participants question the validity of one approach and suggest checking for errors in the calculations.
Discussion Status
Participants are actively engaging in the problem, with some providing guidance on checking calculations and clarifying assumptions. There is a recognition of potential mistakes in the original poster's reasoning, but no consensus has been reached on a definitive solution.
Contextual Notes
The original poster is working under the constraints of a homework assignment, which may limit the types of assistance they can receive. The discussion includes a focus on understanding the behavior of light as it interacts with the lens and mirror system.
- #2
JeremyG
- 62
- 16
Post your working here and we'll help you find your mistakes, yeah? We don't provide full solutions here at PF. :)
- #3
Dhananjay97
- 3
- 0
first i started with the object and the lens and substituted the values in the equation 1/f=1/q+1/p since we know focal length of the lens and the object distance, and got 352.489 cm. This put the image to the right side of the mirror. Now the object of the mirror (the image of the lens) is on the same side as the focal point of the mirror so I solved for q again using the same equation and using -252.489 cm as my p (subtracted 100 cm because that was the distance between the lens and mirror). i got - 76.9907cm which meant the image was still to the right of the mirror. from there i followed two approaches:-
1) assume that the image from the image goes straight to the lens and use -176.9907 cm as p to solve for q to get 38.72 cm to the left of the lens
2) assume that the image from the mirror goes through the mirror again solve for the mirror again, using the same equation but the image kept going further to the right.
1) assume that the image from the image goes straight to the lens and use -176.9907 cm as p to solve for q to get 38.72 cm to the left of the lens
2) assume that the image from the mirror goes through the mirror again solve for the mirror again, using the same equation but the image kept going further to the right.
- #4
JeremyG
- 62
- 16
Dhananjay97 said:
This approach is incorrect. The light ray has already reflected off the mirror at that point, and is going towards the lens. It just appears to be coming from behind the mirror (virtual image).
Dhananjay97 said:
Check your working for this step again. I suspect you might have a careless mistake here.
- #5
Dhananjay97
- 3
- 0
you were right! thank you so much
- #6
JeremyG
- 62
- 16
Dhananjay97 said:
Yup, it's my pleasure!
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