How to Solve IGCSE Lens q with Unspecified Distance

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AI Thread Summary
The discussion focuses on solving an IGCSE lens question where the distance from the beam to the lens is unspecified, only the beam's height is provided. Participants emphasize the importance of understanding the problem's details, specifically the beam's width of 1.0 cm and the need to determine distances on the other side of the lens where the beam width changes. Clarification is provided that a sketch diagram is necessary for visualizing the problem, and participants are reminded to follow forum rules when posting. There is also a note on the importance of showing work or intentions for solving the problem to receive further assistance. Overall, the conversation highlights the need for careful reading of the problem and adherence to forum guidelines.
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Homework Statement
Could you please help me to figure out this question? The answer scheme says i) should be between 0 and 5.6 cm and ii) should be beyond 5.6 cm.
Relevant Equations
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I know a sketch diagram is required for the question but they haven't specified the distance from the beam to the lens. They've just given the height of the beam. So how do I know how far I should place the object? Should the object (beam) be at infinity?
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Read the problem. It clearly states that the width of the beam before it reaches the lens is 1.0 cm. So the question is to find the distance(s) on the other side of the lens where the beam is less or more than 1.0 cm. Should you require additional help, our rules require that you show some work or at least how you intend to answer this question.
 
kuruman said:
Read the problem. It clearly states that the width of the beam before it reaches the lens is 1.0 cm. So the question is to find the distance(s) on the other side of the lens where the beam is less or more than 1.0 cm. Should you require additional help, our rules require that you show some work or at least how you intend to answer this question.
I have re-written how I intend to solve it
 
S2100595 said:
I have re-written how I intend to solve it
Please don't edit your original post if you wish to reply. It could be confusing and is bad form. Start a new post. If you intend to draw a sketch, then draw one and post it. Mind the statement of the problem that says "A beam of parallel light strikes a converging lens of focal length 2.8 cm." What distance do you need to be given to draw a sketch of that?
 
Alright never mind. This is my first post and I didn't realize there are so many restrictions and rules about how I can post on this forum.
 

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