Practice - Combination of thin lenses in contact
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Practice Questions
Test your understanding with targeted questions
What is the formula for calculating the effective focal length of two lenses in contact?
💡 Hint: Think about the relationship between individual focal lengths.
If Lens A has a focal length of 15 cm and Lens B has a focal length of 30 cm, what is the effective focal length?
💡 Hint: What happens when you find the common denominator?
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Interactive Quizzes
Quick quizzes to reinforce your learning
What is the effective focal length for two lenses with focal lengths of 12 cm and 18 cm?
💡 Hint: Think about how focal lengths combine.
True or False: The total magnification of a system of lenses is always less than the magnification of either lens alone.
💡 Hint: Consider how magnifications combine.
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Challenge Problems
Push your limits with advanced challenges
Consider two lenses placed in contact, one with a focal length of 5 cm and the other with a focal length of 20 cm. Calculate the effective focal length and total magnification if the first lens is used as a microscope objective.
💡 Hint: Use the effective focal length formula first, then the magnification concept.
Design a simple optical system using three thin lenses in contact. Describe their purpose, effective focal length, and magnification characteristics.
💡 Hint: Consider what each lens contributes and how you adjust the calculations.
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