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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
What is the lens formula for two lenses in combination?
💡 Hint: Think about how individual lenses work together.
Question 2
Easy
If a lens has a focal length of 20 cm, what is its power?
💡 Hint: Remember the formula for power involves the focal length.
Practice 4 more questions and get performance evaluation
Interactive Quizzes
Engage in quick quizzes to reinforce what you've learned and check your comprehension.
Question 1
What does the lens formula help to determine?
- Effective focal length
- Magnification
- Power of a lens
💡 Hint: Think about what the formula addresses.
Question 2
True or False: The power of a lens is its focal length measured in meters.
- True
- False
💡 Hint: Recall how power is defined and calculated.
Solve and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
A system has two lenses, one converging (f = 10 cm) and one diverging (f = -20 cm). What is the effective focal length and the total magnification if both lenses are used together?
💡 Hint: Consider the signs of the focal lengths carefully!
Question 2
Design an optical system with three lenses where the first lens has f = 15 cm, the second f = 10 cm, and the third f = -10 cm. What is the total effective focal length and power of the system?
💡 Hint: Keep track of the positive and negative signs during calculations!
Challenge and get performance evaluation