Convex Lens Problem: Find Focal Length

Thread starter Siddharth Venu
Start date Dec 20, 2015
Tags

Convex Convex lens Focal length Image Lens Screen

AI Thread Summary

To find the focal length of a convex lens when an object is 90 cm from a screen and the image is formed at two locations separated by 30 cm, one must apply the lens formula and the concept of image formation. The discussion emphasizes that simply posting a question without effort is not conducive to receiving help. Participants are encouraged to use a structured approach and provide their work for better assistance. The focal length can be calculated using the distances provided, but engagement with the problem is necessary for effective learning. Properly framing questions and showing effort is essential in educational forums.

Dec 20, 2015

Siddharth Venu

A screen is placed 90cm from a object. The image of the object on the screen is formed by a convex lens at
two different locations separated by 30cm. The focal length of the lens is what?

Physics news on Phys.org

Dec 20, 2015

Herman Trivilino

Science Advisor

Gold Member

You can't just post a homework question and expect to get a response here. Start another thread, use the template, and show some effort towards a solution. You get help here, not answers.

Thread 'Collision of a bullet on a rod-string system: query'

In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...

View full post »

Thread 'Explain this asphalt sheen'

This problem is two parts. The first is to determine what effects are being provided by each of the elements - 1) the window panes; 2) the asphalt surface. My answer to that is The second part of the problem is exactly why you get this affect. And one more spoiler:

View full post »